I'm running the 74" BA prop on my RV-8 with IO-360-A1B6 (F7497 blades). I have been very happy with this combination. My original reasoning for going with the 74" prop is that the blades can be trimmed to 72" diameter if required for repair, whereas Hartzell does not permit trimming of the 72" prop blades.
I have been extremely happy with the performance. Climb performance is phenomenal, cruise performance is good, and I'm happy with the race speeds this combination gave me at the Reno Air Races last year.
Skylor