up until recently i had 3 wheels plugged in here, an old ms sidewinder non-ffb wheel (no pedals) for steering, a saitek r220 for the down hanging pedals (clutch and brake) and a logitech formula gp (non-ffb) for the brake pedal which i used as the accelorator. (its amazing what you can pick up at bootsales, lmao)
i can honestly say with all three plugged in it made no difference to the FPS at all, however, if FPS drops of 10-15% are a problem to you, i'd consider upgading graphics/system cos as time goes on i should think graphically at least, LFS demands are just going to get heavier, lol
QD