For anyone considering a grip/accessory of some sort, I mentioned this one a while ago:
Quoted for size bitches said:
PDP Trigger Grip. It ran me less than $20 and has been amazing for long sessions. DJ Max Portable 3 has been much more manageable, Ys 7 feels like I'm playing with a PS controller, Katamari is easier to handle (since I have some palm brace-space)...The list goes on.
The only downside to them (like any grip accessory I imagine) is that it makes the system less "portable". My left trigger was a bit funky, but I opened it up and reset the trigger and it worked fine. I called Gamestop to ask what their policy was, and they said just bring it and they would have replaced it no questions asked, too.
That being said, it works like a charm and makes my gaming sessions SO good. Oh, and it makes me less weary about setting my Vita on the table. The case + grips add a buffer zone between the system and any surface, so I'm not as scared to ruin/scratch the back touch. The grip also does a good job of framing the back panel for games that use it (Katamari to stretch the Katamari as an example) so you don't mis-tap the dead zone above and below it.
Definitely the best accessory I've ever bought for a portable gaming device (not counting my iPad 2 slickwrap). Worth the monies for anyone considering grips for your Vita.