thats easy the w7. but if i was you i would still go with the eclipse titanium 15 that thing will kill the w7, expecially because of the price difference
sean, i completly owned a 12w7 with my ti yesterday, this sub is GODLY lol, its amazing, im def saving up for a second one, oh yea, and did i mention, i killeed the w7 with a 1000/1 and i was using a 600 watt rms audibahn amp