jl better quality, but i can say from experience (currently running 2 xenon 400.1) the xenon line is very well built amps. they have never failed me, never once even got close to being hot, and full load 1-4ohms. definately $ well spent. if i had the choice i'd probably buy them again over the jl's, plus the xenon line puts out bigger amps then the jl slash series, and there cheaper. i'd go with them. also they only made them in 2005 so it's not like everyone will be having them.
I'm running three Xenon's in my firechicken right now.. (two 600.1's, and a 1200.1) and I LOVE these amps.. They'll take a beating, too.. had these installed unsecured for a couple weeks when I first got them.. took a few falls into a cargo area, and had them in direct sunlight for 3 straight days (I live in the desert, to boot) and they still perform flawlessly. They'll take a beating.
