I bought the Verizon shell and holster combo at the same time I picked up my 4s. I was hoping that the glass rear would have been left out of this version. I had a friend who dropped her iPhone 4 the same day she got the phone last year. It had me so concerned about the glass back that last night I had a dream that the phone came apart in my hands!
Also, I found i4 and 4s glass backs online for a couple of dollars... So I may just keep a small substock of replacement parts, like I used to with my blackberrys and androids, for those times I do carry it nude.... And not have to worry.