Look at EZ-EFI from F.A.S.T.
Before I got into my (long story, 2-engine) debacle, I had planned to go Mass-Flo and was talked out of it in favor of EZ-EFI, a self-tuning TB EFI. Good reviews, easy to set up, great mileage, and without all of the tuning hassles of some of the SEFI setups out...