go find a local shop and demo them....and then buy from that shop...dont be a jerk and milk them for advice and resources and then buy everything on line,
My local shop has a pretty standard demo room, where you can do A / B compares between speaker sets. It is not 100% perfect, but you can get the idea of how one speaker sounds compared to the other.
Most important.......buy from that shop...something for their trouble. Don't be a jerk and waste their time, and then go buy from crutchfied just to save $10.