I agree with boonman, Vito's pitons are made from wiseco. Vito's takes the pistons and modifys them for different set ups. Vetos's changes the widows adn the bottom of the skirts. By doing this it not only changes the port timing but it lightens the piston to help with hp and a lil quicker rev. So your question is not what piston to use(vito's or wiseco) but how are you trying to set the bike up(top-end, bottom, mid range). What ever pistons you get make sure you let the shop know what kind of riding you do most and what you want performance wise. I would just call Vito and tell him what you want.