i had a stage 3 and a 9lb flywheel on my gsr and it was borderline too much.. in traffic i wanted to blow my car to pieces i got so annoyed sometimes. it will rev fast and there isnt really any "play", it just grips and goes. combine that with fast revs and you got a nice launch.. but you dont wanna be launching off every stop light, stop sign and in traffic..

stage 4 w/ a 7.5lb flywheel is no where near comfortable in my opinion.