I'm considering getting on the Vita for the portability and the OLED screen but on the PS3 the bigger screen would make it better to sell all the details Vanillaware puts into the game.
I think for me it will depend on the size of the characters during gameplay.
The thing with Vanillaware games is that they are so beautiful I want to appreciate them the best way I can.
Off topic, I'm glad Muramasa is getting a jump button. I liked it on the Wii but ended up no finishing it, I probably got sidetracked by some other game. Also, I loved Odin Sphere and it took me literally years to beait it, I just wish some bosses weren't so hard, especially the ones that loved spamming status effects on you.