The testpipe alone made a big difference and people say the dp makes an even bigger difference. I cant wait to put my dp on (in 3 weeks hopefully). Personally i cant justify the price difference between the 2. Also if name brand matters to you look into AMZ dp and tp... they are a little cheaper than super split. For the clutch i would get rPS Street... should be good enough for stock turbo setup. I had it on my previous Z and loved it. Also get lightened flywheel... people have said it makes a pretty big difference.