i had a CES installed once upon a time ago, i certainly felt a difference in lift after i installed it, however your quite right- it drones badly. I went back to stock after about 2 months with it on (had to swap over as i started work at 5am and couldnt stand hearing the exhaust drone so early in the morning). Dont worry though, if you put it up for sale in this forum, it will get sold in a heart beat. mmm well i had ported headers and exhaust done... Top end 'may' have felt a bit better but it certainly wasn't a big difference... very subtle. It's weird how some ppl say it drones and some ppl say it doesnt... i wonder if there is a way it has to be installed.