This is a great filter, I loved my original Flip-Up for my Gopro 3 and this one is for my Gopro 3+. It comes with an adapter for 3+ so you can use this mount for both camera.
Only thing I don't like is that once you mount the filter, it is difficult to open the camera on the Gopro 3+ case, you need to use something like a key or screwdriver to lift up the latch as it is very tight and you can't get to it easily like the Gopro 3.
Other then that, it is a great filter and I highly recommend this over switch blade.
This is a wonderful device for scuba divers. I have used this for a week and have downloaded over 6 hours of underwater video using this device. I would highly recommend using it for the ease of flipping the filter open while above the water and pulling the filter over the lens while under the water. You will not be disappointed.
My only improvement would be to add the sock that backscatter sells to keep the filter/housing safe. The filter is easy to flip around, and with the LCD on a Hero3, the footage is always exceptional. We've used it in various Hawaii waters, and being able to flip the filter off so easily has been invaluable. It has been much more durable than other clip on versions we've tried.
First of all, the image is incorrect. The product is actually the Backscatter Flip 3.1. I have not tried it yet, so, I can not tell anything about the image quality underwater. There are plenty of good comments about that around the internet. I can tell instead, that the product is really well built and seems to last long. The filters seems to be of good quality too, but need a careful handle.
I'm using this for shooting underwater video in a river system in a few inches to a few feet of water. It's GREAT! It was extremely easy to install and is well built. The design allows for less than a second to flip the filter on/off the lens, swinging it back against the side of the camera when not in use. It does not, in any way, impede the view of the lens when on or off (no dark corners in the frame or other visual anomalies introduced). It cuts the glare when shooting in the general direction of the sun and the color correction DOES work, which means significantly minimalized post-processing time for me. Love it!