I put my single turbo kit together for under 2k..the install was a lot of fun...also a lot of work...everything had to be customized. EVERYTHING. I can't remember if you said if you were still seq or not but the way I see it is if you are happy with the power of seq than 100% stay that way, at least untill they break. If you wanted more power and were leaning towards non seq I would say definitely go with a single...if you are going to deal with lag you might as well get a heap more power, instead of just a bit more while giving up a ton of low end.