HIm running the Beps256. Same specs but in the bolt on housing. And I reached 51lbs/m no prob at 26psi. Boost biulds quick and at 26psi it puts you back in your seat. The .63 housing should be even more fun!

In thoery the s256 is the same size wheels as the hx35, and gt30r.. But the extended tips are sapposed to make a huge differance.

Also so far with my experiance with the last 2 Borgwarners ive tried to identify. Borg Warner dosent release compressor maps and data for their turbos as much as Garrett. And have been known to underestimate their own turbos. Rating them based on diesel engine hp numbers. Sorta like how a gt30r is rated for less power on a subie motor then a DSM motor. And there isnt alot of research with BW turbos on 4g63s.

A few people including a couple turbo gurus believe the s256 is way better then the hx35 and a good compatition for the gt30r.
Anyway.. That is my ealry morning breakfast 2cents!!