I am surprised that there are only two battery companies being talked about here. My choice for any vehicle and especially ones where car audio is a factor would be Batcap hands down. My buddy runs his car and about 1500 watts (2 amps) off of their Batcap 800 with never any problematic voltage drops ever. The 800 is like a mini battery. Their 3000 would be a perfect fit for your application and would provide more reserve than you will probably ever need. Now if you plan on running your system without the car running for long periods, which I think you said you would not be, the two previously mentioned might be better choice. My .02 and keep in mind I'm no battery expert.