So, I took the jump and ordered the PRS 650, for ebooks and manga (YEY!)
So one of my intended uses is a bathtub, pool reader

Now, as I dont trust my capacity to keep a regular $5 book above water (im a clumsy, clumsy person), I am sure not gonna try with a $200+ piece of electronics, unless I am VERY certain it wont get damaged. So I ask, wich case is good for protecting my investment?
Close fit is not a must, since its only an occasional use.
Padded for bumps would be nice but not a must.
Submersion proof Is a must. I wanna know for certain that it wont fail if it drops to the bottom of the pool.
So there, If you know of a case that complies, please let me know, and thanks in advance for the answers!