I opted for the 800.4 with each set of xm9. Only one set now until i can hear what it sounds like. It just gets so hot here, compartment temps of 150+ are not uncommon. Brian recommended against the harpoon and to go with two amps that wouldn't have to work as hard. Guess I could have gone with two harpoons lol. I also got a zld with the kit. I wanted the big12 with the 1500.1 but the big12 was on backorder about 3 weeks ago when I placed my order. I'm going to end up with 4 amps in this boat probably, but should be super efficient.