I have over 2500 watts. 2 eclipse XA2000 amps, reworked for 750 watts each rms. eclipse EA4100 reworked for 250 watts per channel rms. 2 Image Dynamics IDmax 12d2 subs, sealed enclosure with acoustic fiberglass matte for standing wave damping. Vifa made Eclipse 8070 7 inch midbass drivers in each door, Morel MT-23 23mm tweeters cut into the A-pillars. 500 watts per corner in the front. Eclipse AVN6620 navigation based source unit with 5volt preouts. Second Skin Damplifier Pro sound damping, in 2 layers, throught the vehicle. Total weight is over 400 pounds.
I don't have battery issues... at all. The only time I notice significant drain is when the outside temp is over 100F. Then the batteries don't like to charge. Other than that, I dont' notice anything.
my build
SoundDomain: 2006 Honda Civic Hybrid