i have a friend who put together his engine in about 2004 or 2005. it got tuned on the stock twins to 390hp, and then he upgraded to the other Apexi turbo kit (its not the Rx6, its bigger, very rare kit), and it does 390hp@15psi.

i think its only got about 10k on it, but he drives it HARD. its actually F-ing scary. he just posted a video of an 180mph+ pull, it sees a lot of track time too.

the engine was mostly new when it went together.