Roger, I have said this one before (agree with you): used to be true you could build a SB chevy for cheaper. Sometime in the last five years SB Fords have become ubiquitous, just like the chevys. As a result, prices have come down. Nowadays, you can almost see SB Ford builders on every street corner--this definitely was not true years ago. I attribute the popularity to NASCAR and the various Ford programs in NASCAR.
Now for HP, it was true before, you could make plenty or more than a chevy, (just cost more); but today, you can still make more--it just costs less.