I almost got that pouch until I stumbled upon the case I got. I really like the extra space the pouch has, but the Hori case has a hard outer shell. It was a tough choice, but I went with the Hori in the end. Either one is a great choice. Ideally, I would want the FEB case though. I just don't think they will sell it separately.
Main reason I went with the pouch was the extra space. Seems like people will need to be carrying their AC adapters around with them, and most cases don't have space for that. Plus the pouch holds a bunch of games and other stuff.
As for the Vita, I'm considering a shell for it, besides the screen protectors. Although as some have pointed out, shells can collect dust which can be a problem.
Would be nice if Otterbox made a case for the Vita, I have one for my Droid X and its fantastic; completely protects the phone from most potential problems.