The XP 1, 2, and 4 are cheaper then Big Al's, at the moment.
XP1 FilStar Canister Filter $63.99
XP2 FilStar Canister Filter $79.99
XP3 FilStar Canister Filter $103.99 ($89.99 ay Big Al's.com)
XP4 FilStar Canister Filter $159.99