I picked up the the gel cover at the Sprint store on Friday. I'm sure it was over priced, but I was buying the phone off-contract, so it didn't really seem like that big of a deal (plus the Sprint employee didn't charge me an activation fee on the phone...)
With the exception of the bump at the base of the phone, it is still slimmer that the Hero that I just upgraded from. Taking it on and off the phone for the past couple days, I feel that the extra bulk that it adds is more than acceptable for the protection that it will provide. I never had one for my Hero, and while it has held up reasonably well it definitely has battle scars. Even with the case it still feels smaller than my friends EVO and all of the uncased Epics that I've seen.