Well, my partner Andy Mullins and I have designed several turbo kits around the Borg Warner/Bullseye turbos now. I guess the first thing you really need to know is what your power goals are and what spool up goals are. The Bullseye turbos are the ones I have used. EXCELLENT customer service and they really stand behind their turbos. They use Borg Warner/Airwerks box units and components for their turbos.

Some of them (the cheaper ones) are just Borg Warner box units. The one that sounds like it would fit your needs is the S256. You can get a box unit for around $950 brand new. They have them in a couple different AR sizes, a couple different turbine housing options. We have made 400 at the wheels on these with zero issues and around 22 psi on a Subaru motor. If you decide later that you want to upgrade, you can send it back to Bullseye and they can upgrade to the S259 compressor housing and Billet wheel!! The S259 is good up to around 550-600 at the wheels.

Characteristics of the Bullseye Power turbos from my experience:
-Fast spool up
-Stable boost
-More power than similarly sized Garrets after around 20 psi
-Excellent response between shifts
-Cheap to rebuild
-easier to upgrade in the future
-custom wheels
-stainless turbine housing options

If it takes 30 psi on one of these to make 400 hp, you are doing something wrong or you have a 1.0 liter motor, lol.