I've played the game on both platforms and i find the PS3 version to be much easier because of the bigger buttons and larger screen. On the Vita i had a hard time getting the timing right because the characters and the button prompts are smaller, the tiny face buttons on the Vita doesn't help much either.

I tried playing with the touch screen but i felt like my thumbs were obscuring most of the screen so i couldn't see which enemies were coming up next. Maybe it's easier with the Vita laying flat on a table and tapping out each beat that way.

Anyone else have a personal preference?

I downloaded it off my friends account on my PS3 and forced him to beat it for me. I hate the game though (Because I suck at rhythm games) but I'm positive he prefers the PS3 version.