Pretty da*n loud they say 1000 watts max each but @ 2 ohms I cracked the paint off my roof with 4 of them they sell on ebay for around $50.00 each and also what do you think of a 1000 watt 4 channel Lanzar vibe amp
I wouldn't use max power ratings.. stick to RMS, since that's the continuous power they can take without incurring thermal damage.
the audiobahns will get loud, and probably not fall apart on ya, but they aren't known for good sound quality at high output. generally the louder they get, the worse they tend to sound.
if all ya want is cheap and loud though, they'd serve well