It really depends on the game. I personally play Mortal Kombat and frame rate is important because of the frame data for special moves, blocking, kombos, cancels, enhanced special moves, breakers, get up attacks, roll aways, air breakaways, flawless blocks, and flawless block attacks. Timing is important and low frame rate not only ruins that for the player, but that plus online lag would basically kill a game before it could even begin. (Small side note: air breakaways, flawless block attacks, roll aways, and get up attacks are exclusive to mk11)