it totally depends on what you want to use your car for road,track,drag,hill climb, in my opinion the hks 2510, 2530 turbos are a good compromise between low rev grunt and hi end squirt with stomping mid range, however because the hks turbos are ball bearing and water cooled, they are much more expensive than say the trust t517z's which have about the same mid to top end power of the hks twins but with the response of say the standard turbos or very close to it. the only thing that goes against them is the fact that they are the old plain bearing type and only oil cooled, but i have read articles in japanese magazines saying that they are actually more reliable than the hks turbos, go figure any way i hope that helps you out a bit.