I used to use the kicker zx2500.1's (2 of them) and i switched them out for rockford 30001bd's and havent looked back... the rockford build quality is better, the rockford looks better (in my opinion) and was MUCH more powerful (as it should be, with birth sheets at around 3700 watts each vs. the kickers 2600ish #'s). The rockford website shows that the average birthsheet on a 20001bd is around 2800 watts, so its pretty comparable to the kicker.... I would go with the rockford, but either one is a nice amp....