MemphisMechanic, you are right about spring , heavy bullet, and fast burn powder. But, I have expiermented with that combo of fast powder with 125 and 147 projectiles but didn't like the snappy feel.
I'm in the WSF camp. I found WSF is perfect for me in 9mm. It has a push feel that i like, and I agree with Blackhand that a WSF load is very accurate.
I believe it's all subjective, so use what you feel confortable with