[DonC]

Put a Mass-Flo system on my FE over the winter and am very pleased with the results.
Dynoed with the carb installed before I started and again after the Mass-Flo was installed. Gained 25 hp and 15 lb/ft. Actually though I'd loose a little so was pleasantly surprised.
A couple of teething problems when I first ran the engine after the installation in that it was running too lean. A couple of phone calls to Chris and following his advice to get into the ball park and, when the dust settled he burned a new chip for me and I haven't looked back since.
Major difference in the dyno sheets when you look at the hp and torque curves. The EFI results are extremely smooth and consistent compared to the carb print outs.
Relatively easy to install and everything needed was included. Went with his fuel system also.
Had a chance to try it at altitude at WSCB when we went over Mt. Rose (8-9 thousand feet) and I couldn't tell the difference from sea level. No longer have to make estimates on how many pumps of the gas pedal to give it before cold starts to get it to fire up, just turn the key.
DonC