I'm going with a CT-27 from ATS Racing, but I won't have a power figure until some time in July. The MR Controls Power Primer and the KO Racing websites both have guides to increasing power before you get into reinforcing internals. The feedback from the Neal Bates guys in Canberra is that they don't recommend more than 1 Bar of boost (14.5 PSI) without fitting a BEAMS block. Some of the bigger gains reported will be at up to 22 psi.