I got this camera as an upgrade to my beloved D5100 so the bar was pretty high and so this review is often D5100 vs. D5300. I'll be frank. The D5300 outclasses the D5100 so substantially that it has utterly obsoleted the D5100. Ignore those who say that the D5300 merely provides an opportunity to pick up a D5200 or D5100 for a bargain price. No. The D5300 is now the ONLY camera in the Nikon D5xxx line. It has changed the game. Don't bother counting pennies, this camera is underpriced at full price. The fact that I am sincerely comparing images from this $800 camera body to my D800E's images truly says it all.
Please allow me to just get into the Pros and Cons:
1) PHENOMENAL IMAGE QUALITY! AT LOW ISO THE D5300'S IMAGES ARE ON PAR WITH THE BEST CAMERAS IN THE WORLD AND THAT IS NO EXAGGERATION WHATSOEVER. I can't believe there is still a debate going on about the efficacy of Anti-Aliasing filter removal. I'm sorry, but the difference is so noticeable there is no debate. And moire was a myth even on the D800E, which I do also own. I guarantee you that you will find more moire in a D5100's or D7000's images than you will on the D5300. Color and saturation from the D5300 are exceptionally good versus ANY camera at any price point. Now, I will still take the D800E's images over the D5300's but it is not at all night & day. They are actually surprisingly close at low ISO.
EDIT 2013-12-09: Photographing cats a lot I am catching a little false color on shiny fur. Nothing of concern to me though.
2) Focus point spread (area of image with AF sensor coverage) is MUCH greater than in FX ("full-frame" sensor size) cameras. The D5300's AF point coverage extends left-right top-bottom much farther than FX cameras. I would estimate the D5300 covers probably double the area that FX cameras do and this is an ENORMOUS advantage. I always leave my D800E's focus point glued to Center because the AF coverage is only in the center area anyway so why bother with the other 50 AF points when they just don't cover anything? I actually do use my focus points on my D5300 because they cover the frame pretty well. I'd still like to see even more coverage, but vs. the FX bodies, APS-C cameras have a tremendous advantage.
3) Minimum shutter speed in Auto ISO now has AUTO setting that adjusts based on focal length! This is SO much better than a fixed shutter speed regardless of lens length.
4) Hard to quantify but the HDR images look much nicer than the D5100's and the Extra High setting is intense and beyond the D5100's abilities. I have not been able to verify this but it *appears* as though there is now image alignment for the 2 photos used for the HDR image as my handheld HDR shots nearly never look like 2 images whereas they often did on my D5100 at full or nearly full magnification. HUGE improvement!
5) Great-for-DX and pretty-good-versus-FX ISO performance. I'll put this to bed right now; the D800E smokes the D5300 for high ISO performance. Sorry, this is a different league. However, the D5300 substantially outperforms the D5100 at ISO 1600+. The improvement in the D5300 over the D5100 is readily noticeable.
6) Much more intuitive i Menu. The D5100's i Menu being J-shaped was ridiculous and totally awkward. I never got used to it after thousands of photos. The D5300's standardized 2-lines-across-the-bottom Nikon style is a drastic improvement.
7) GPS! I don't know what Nikon was thinking with that clunky expensive GP-1A. Did anyone ever buy one? The D5300's internal GPS works great and hooks up quickly and I'm big on geotagging so I am super stoked to have this on a REAL camera!
EDIT 2013-12-09: I spent a day in the country (wide open clear sky) with this camera outside of my normal metro town area and despite using A-GPS data, it took somewhere between 30-60 minutes to get GPS lock. Surprised, disappointed. But that was the only time I have had trouble with hookup.
8) Nikon's had truly exceptional built-in flash performance since at least the D90. The D5300 does not disappoint and bests or matches its predecessors at any price point. This could be a result of image processing more than flash performance but whatever it is, using flash is a joy, not something to dread.
9) The red body paint color is super-gorgeous! It's like a candy apple red Corvette color and it is way sexy.
10) The new bigger, higher-pixel screen is REALLY nice. It is not insignificant like many reviewers dismiss it as. I like it a LOT. :)
11) EN-EL14a battery with 19.4% more capacity is a nice treat and helpful when running GPS and/or the silly WiFi. I have not spent a full day shooting hundreds of photos with the D5300 yet but I have shot perhaps 100 shots in a day with GPS on and flash here and there and a lot of reviewing and in-camera editing and not gotten below 2/3 battery level in a day.
EDIT 2013-12-09: GPS was on from about 8:45am to 5:30pm, WiFi was off all day, I shot 362 photos (almost all were 14-bit RAW+Large Basic JPEG so roughly only about 170-190 shutter clicks) and probably 15 of those photos had flash, 2 minutes of video, edited 6 photos and had a couple of review sessions during the day. Battery level fell to 1/3 remaining. Not bad but could be better. If you're a heavy shooter and will use GPS and/or pop-up flash, carry a spare battery.
12) Here's a gem for the old-school film guys like me. ;) Or a little "secret treat" for digital-era photographers with a true creative streak. In Manual exposure mode, the "T," or "Time" setting has returned! Want to take a 5-minute or 5-hour exposure but you left your plug-in intervalometer/timer at home? Lol, as if you even have one... No problem. Turn your shutter speed dial all the way past 30-seconds, past Bulb and click on into good ol' Time at the end of the dial. Press the shutter button to open shutter, let your wristwatch or phone tell you when exposure time is up and then press shutter button again to close the shutter. Seriously?! Yes, seriously. How cool is that?! I miss this so much and guess what? Even my D800E does not have T and the D5100 does not either. According to the Nikon info page for the D5200 (Yes, D5200. Not a typo), T is there but you need the ML-L3 remote to use it.
1) EDIT 2013-12-09: I have found that focus points other than THE Center focus point are somewhat frequently inaccurate. Focus points at or near the left and right edges are rarely accurate and almost never dead-on. If you use ONLY the Center focus point, focus accuracy is quite good and consistent. As Center AF point AF-S is almost always how I shoot, this is not a deal-breaker for me but it is certainly a handicap. If you use multi-point AF tracking or regularly venture away from Center AF point, you had better experiment with different AF points at a local camera store before buying one from any store, Amazon included. I am beginning to think my camera may be defective and will likely send it to Nikon for repair or exchange it with Amazon for a new one. Honestly, I expect this to be a performance trade-off that Nikon will not remedy. Though $800 is not cheap, this caliber of image quality for $800 is going to come with trade-offs and I bet being forced to use Center AF point is one of those trade-offs.
2) EDIT 2013-12-09: I had a chance this past weekend to use Live View in some beautifully sunlit countryside. Sorry, even with truly ideal lighting Live View is horribly slow and constantly hunting. Don't use it for anything other than manual focus confirmation with screen zoomed for precise focusing. And focus VERY slowly as screen update time has substantial lag. I'm not really concerned about video, but this camera cannot focus worth a darn for video. It really is that bad, sorry.
3) When reviewing a photo on my D5100 and even the D5200, I could just press the OK button to get into Retouch Menu and then get into RAW processing of that image in another click of OK. Boom, 2 presses of OK and I am RAW processing the image I'm looking at. Well, not anymore. Now I have to press the "i" button to get into Rating/Retouch/Send Menu and then click OK to get to Retouch Menu and then another click of OK to get to RAW processing. Hardly a nightmare but takes an extra button press and, more importantly, is ergonomically awkward and more prone to mistakes.
4) Noisy Multi-Controller. I like having solid clicks, but man, clicking Up, Down, Left or Right on this Multi-Controller is literally enough to wake someone up. My gf grumbles at me for reviewing/RAW processing in bed because of that. It's also not so great in public areas as it intrudes on the conversations of neighboring tables, etc. It's really an irritating higher pitch that grabs attention. I know this complaint sounds whiny, but it truly is an intrusive noise problem.
5) WiFi is rubbish. You can't upload full-resolution images to your smart device via WiFi. And I don't believe (but I could be wrong about this) that you can WiFi upload at all to a PC. I wanted to have instant constant file backup via WiFi. Nope.
6) Slow RAW process Menu navigation. Perhaps it's the sheer file size but things like scrolling Picture Control modes in RAW processing is very slow relative to the D5100.
7) Slow photo review after taking a picture(s). Takes too long for the D5300 to gulp down one or a few RAW+Large Basic JPEG shots (my standard resolution).
8) After assigning HDR function to the BKT button (D5100)/Fn button (D5300), activating HDR now requires holding the Fn button and turning the dial until you get the setting you want before letting the Fn button go. On the D5100 you set your HDR preference one time in the Menu and then activation via BKT button only took a single press. Now it's a process. And my favorite setting (High) takes the most clicks (3 to the left or 3 to the right) to get to. The Auto HDR mode should simply be removed so we just scroll Low, Normal, High, Extra High and should be permanently Menu-set to facilitate 1-press activation a la D5100.
9) To get autofocusing you MUST use an AF-S or AF-I lens. D5300 body has no focus motor for AF or AF-D lenses. Metering requires a CPU lens.
The D5300 is not a camera for sports, when rushed or in demanding conditions and you are gambling when you change away from Center AF point. Many consumer cameras like to claim performance in this fast-action realm, but no. If it's not pro gear it will suck at sports and tracking a subject. Always has been and likely always will be the case. However, for general photography, landscape, portraiture/still life, macro, time-lapse, etc. the D5300 creates stunningly sharp and colorful images able to be painlessly enlarged to enormous proportions. I wouldn't hesitate to print 3-foot x 2-foot (that is 36x the size of a 4-inch x 6-inch) prints. And that would be essentially pixelation-free. 6-foot x 4-foot would still look fantastic.