I got this so that I wouldn't have to worry about taking my DX out near the pool in the summer (and so I could read while floating!). I haven't actually had a chance to test this case yet, but it appears that it will perform exactly as described. The case is made of thin, flexible, but apparently strong, plastic. The front is clear, the back has a slight blue hue. The DX fits inside with plenty of room left over - this is NOT a fitted case, it's more of a pouch that you'd put the Kindle in, or could use for other electronics as well. The top is well-sealed. There is a heavy plastic foldover that has two snaps and a strip of Velcro holding it closed. Inside that foldover is the actual opening of the pouch, which seals with two ziplock strips, then gets folded into the hard plastic part. It seems very secure. Several reviews commented that you had to undo all the seals to turn the Kindle on. I got the brainstorm to put the Kindle in upside down, and discovered that you can use the on/off switch through the thin plastic body that way, which seems to me that it would be more secure than opening the watertight seal at the top to turn on/off. There is an adjustable lanyard attached at the top, so you can put the sealed Kindle around your neck or something to avoid any accidents while on a raft or tube.
All in all, I'm looking forward to using this in and near the pool this summer. It looks as though it will deliver exactly what it's supposed to, and I'll be considering getting another one for my smaller Kindle as well.