I just got mine back and decided to add a few goodies as well. I also added their doolz, stage 1 turbos, split down pipes, ported/ground exhaust manifolds, and the ecu to match it all. All I can say is HOLY S@#T!!!! This car is a totally new animal. As far as the swop, I did not get a brand new or rebuilt engine. I got a "long block" with about 60k on it and it feels brand new compared to the last engine, when it ran well! Z1 would be my choice. Good luck with your decision.