i have never done a direct comparison but i have heard tons of subs.

i don't like the klipsch subs, they jsut sound bad - they don't go very deep either.

velodyne's seem boomy to me and chuff a lot

paradigm's - don't remember, but i think i remember liking them

the ep350 is a fine sub but i hear the ep500 is a very nice upgrade.

the only other sub company out there you forgot about was SVS - they make good subs for good prices