I have U3415W and U3417W in a dual-monitor setup, so I'm just going to comment on the differences.

The two main differences are:

- Less backlight bleed on U3417W. Most noticeable in a dark room viewing dark content. U3415W is not the best choice for watching movies full-screen.
- Greater curve on U3417W. U3415W is slightly too flat for a monitor of this width. This matters mostly in a multi-monitor setup, where you might not always be sitting right in front of the monitor. As a single monitor, U3415W is fine.

Both differences make U3417W better. Not worth the current 50% price premium, but clearly better.

There are other, smaller differences:

- Thinner bezel on U3417W. Approximately 10mm on U3417W and 13mm on U3415W.
- U3417W has two USB ports on the side and two on the bottom. U3415W has one on the back and three on the bottom.

Needless to say, both monitors are great. No discernible difference in picture quality.

I have been looking at the new 34" widescreen class of monitors for about 6 months. I was initially excited about the LG, but after reading many complaints about its light bleed and other quality issues, I decided to wait. For reference, I am using this as a home office monitor hooked up to a recent MacBook Pro 15" via Thunderbolt -> Displayport running at full resolution at 60hz.

Appearance: Winner Dell
Both monitors are nice looking. Dell has a flatter, simpler bezel that disappears on the sides when the monitor is off. The Samsung bezel is more pronounced, though still nice looking. I consider this a marginal win for Dell and highly subjective at that.

Ports: Winner Samsung
While Dell has a greater variety of ports, including two upstream USB3, MHL (which I have no idea what to use with), and miniDP in, in addition to regular DP, and HDMI, I really appreciated the Samsung's two HDMI inputs. This allowed me to run two different HDMI sources in for the PBP/PIP function, namely an Amazon Firestick and a DirecTV box. I also prefer the port arrangement of the Samsung, which has every port on the back and facing out and away from the back. The ports are substantially easier to get at and they work better with a monitor arm (or any cable management device) because they tend to point out and away from the monitor and towards their source rather than down, which requires a sharp turn to stay out of line of sight. The sharp turn of the chords on my monitor arm for the Dell arrangement (down facing ports) actually puts enough pressure on the arm joint that I had to adjust it to avoid inadvertent swivel. And even though the Dell ports are well labeled, it still hard to get stupid non-reversible plugs in without being underneath the monitor.

PIP/PBP: Winner Samsung
Both the Dell and the Samsung have similar PBP/PIP options in general. The Dell offers a neat feature wherein you can tie different upstream USB inputs (two are provided) to different inputs (e.g. to control different computers peripherals). However, the Samsung is more functional in a variety of ways. For the Samsung, you can characterize each input so that the resolution is a better match for the source, e.g. you can characterize the HDMI input as an AV source rather than PC, and get a better formed 1080P picture. The Samsung also has much better sound options for the PIP windows. A critical flaw in the Dell is that while you can set the sound source to either the "main" window or the "sub" (i.e. PBP or PIP), there is no way to tell the monitor to default to one or the other when turning on the PBP/PIP window. What this means is that if you use the PBP/PIP for TV, every time you turn it on, you then have to go deep into the menu structure to turn sound back on. This is very annoying for a feature I want to otherwise use frequently. My recollection is that the Samsung allowed me to set this up such that any time the PBP/PIP window was on, it had sound priority.

Menu Structure and Control: Winner Dell
The Samsung uses a joystick on the back that you have to "click" in to make selections on, while the Dell has four buttons on the front that are some sort of capacitive sensor activated or the like. A nice feature of the Dell is that you can set two of the four soft-touch buttons as shortcuts to frequently used features, such as sound level, PIP/PBP, input source, etc. Unfortunately, you cannot set one to a shortcut to sound source, which would at least mitigate the problem discussed above. Overall, while I find neither totally awesome to use (and there is no Dell monitor software for Mac), I preferred the buttons on the front of the Dell to the joystick on the back of the Samsung. The Dell arrangement works better on my monitor arm because with the Samsung I would always upset the arrangement of my monitor on the arm while fiddling with it, not to mention that it was harder to reach on the Samsung.

The menu structures of each are fine, though I find the Dell to be slightly simpler and more straight forward, though the Samsung has a greater variety of features, in particular AV related features.

Stand: Tie
Both the Samsung and the Dell come with decent stands. As mentioned above, I use a monitor arm that was able to hold each easily with a VESA 100x100 attachment.

Sound: Winner Dell
Both the Samsung and the Dell have adequate sound. The Dell has slightly more powerful speakers (2 x 9W) versus Samsung (2 x 7W). I think the Dell sounded slightly better in a TV and music test, but this is highly subjective.

Viewing Angle: Winner Dell
I had read that the VA panel on the Samsung would probably have worse viewing angle as compared to the IPS panel on the Dell, but I did not expect it to be as severe a difference as it was. With the Samsung, especially with a test pattern, you could see major color shift even just from one side to the other without changing view position. When changing view position, it was much more pronounced. When looking at one test pattern, whitish grey lettering became noticeably tinged with pinkish purple towards the edges. And when viewing any sort of picture, tv, etc., the Samsung was much more sensitive to viewing position changes. While the Dell also suffers from a bit of change when changing position, it was much better from a fixed position looking from edge to edge and also held its color uniformity much better when changing viewing position.

Colors: Tie ... once calibrated
I think both monitors can produce great colors. However, the Samsung does not come calibrated from the factory and the original settings looked pretty terrible. Luckily I had read about that before I bought it so that I did not immediately package it up and send it back. I do not have professional calibration equipment, so my calibration was based on reviews I have found online and my own preference, but I think both perform really nicely. A really nice thing about the Dell is that it comes with a calibration report from the factory and comes out of the box in very good shape. There are still adjustments to be made based on taste (particularly with respect to brightness), but I think both can achieve similar performance.

Black Level and Light Bleed: Winner Samsung
VA panels have an advantage over IPS panels (read: IPS glow) in terms of black levels, and this was apparent. The black level on the Samsung was significantly better than that on the Dell when calibrated for similar brightnesses. With that said, it does seem like the Samsung exhibits a bit more "black crush" in dark scenes.

As for light bleed, the Samsung blows away the Dell. There is almost no discernible light bleed on the Samsung while the Dell definitely has the tell-tale corner bleed. It appears to be better than the LG, and it is not so bad as to make dark scenes unenjoyable, but when looking at a flat black background, the Samsung is far better.

Text Clarity and Sharpness: Winner Dell
You may have noticed that I liked a lot about the Samsung and thought it better than the Dell in many ways, but this was an absolute deal killer for me. I could not, no matter how much tweaking I did, get the Samsung to have crisp text. It was either not sharp enough, such that the text appeared fuzzy on the edges, or it was too sharp and looked to have the artificial white halo--particularly on smaller text. I think this may have something to do with the fact that the pixels on the Samsung are in an elongated orientation, whereas the Dell is more typical squarish orientation. As I mentioned before, the Dell came out of the box just right, while the Samsung took lots of tweaking, and I still couldn't get it right. Ultimately, the text clarity bothered me so much on the Samsung that I ordered the Dell, and now I have the Dell and the Samsung is on its way back. I suppose there is some possibility that it is my Mac that is a part of the issue, but I have a hard time believing that given my Mac has looked great on many other screens.

Overall Winner: Dell
Though I really liked the functionality, port arrangement, and black level of the Samsung, ultimately the text clarity and much better viewing angles of the Dell won me over. I hope that Dell will consider giving me a better sound control option, but I doubt it. I will just have to live with it until a reasonable 34" 4K monitor comes around!

Here is a link to a flickr gallery with pictures: [...]. I have also attached the photos here.

I bought this monitor to replace 3 aging widescreen 22" monitors I've had since 2007. I had some reservations if this single monitor would be able to adequately do the job. I was not disappointed. The real estate of this Dell Ultrawide is amazing. You can fit 3 windows in a single screen with enough information to still make it usable. The clarity and precision is also great. I'm a software architect by day, so I need as much real estate I can get to program, respond to email, and chat with my team. This makes it all happen with ease.

I really wanted to love this monitor. I've tried LG and Samsung's versions and they weren't quite up to snuff so I happily dropped $1100 on this monitor (I bought it a few months ago, before the price crashed). I was sure that it would be very high quality, and the 3 year warranty gave me extra peace-of-mind.

There is a lot to like about this monitor: you couldn't ask for more inputs, the built in USB hub is great, the stand is nice and sturdy and the picture quality in the middle of the screen is phenomenal.

Unfortunately, my monitor has MASSIVE backlight bleed - see the photo below. If you want to use this monitor for web browsing or data entry, you will be fine. However if you are a creative professional and there is the slightest chance that your work will entail any colors other than white or yellow, you have to stay away from this monitor. The backlight bleed is that bad.

Unfortunately, Dell's service has been equally useless. Their phone support literally hung up on me, and their web support is currently refusing to do anything for me because they made me send them photos of the monitor with a light background under "normal office lighting." which conveniently masks the problem.

Sorry to break it to you, Dell, but creative professionals (photographers, videographers, etc) don't use normal office lighting. My studio is kept dim for a reason. And it doesn't matter if bright colors wash out the problem - the vast majority of my work involves dark colors somewhere near the edges.

If I could return this thing, I would. But for now I'm stuck because Dell refuses to honor their promise to their customers and I can't ethically sell such flawed product to anybody else