I just hooked up a jl audio 500/1 to a mtx 9500 in a friends car and it really pounds.. for the L7 though I would put a Kicker 750.1 or a 1000.1 on it if your wanting to go cheap.
if it was me i would go JL audio because of the thd = .05% and 1000w at any ohm load between 1.5 - 4ohms. the alpine pdx amps are nice, but they do get really hot, so if u do buy them they say there stack able but i wouldn't do it because it just gets so hot.
you can find kicker amps online really cheap under refurb sections.
and the hifonic's amps arn't really crap, they just have a really high chance of noise, and distortion. they are cheap power, and when buying audio equipment always remember, you get what you pay for