on the track or on the autox course you should most definitely feel the difference if the splitter is made correctly. I.E. isn't too flimsy, actually goes to the front of the wheel wells at least and probably has about 3 inches extending outwards...(at least). this all being said if you don't have track experience yet, (which you may very well have lots for all I know), but if you don't, then you will have no idea how much of an effect it makes. you won't know whether it's you getting better as a driver or the splitter doing the work. I will say that if you don't have some sort of slight rear downforce enhancement to offset the added front downforce you will be receiving by adding a splitter, it may have an adverse effect on your handling.