I have a 2007 X2 and with just the jl 6450 and a jl audio mhd750/1, still waiting for the mhd600/4, wordwide backorder
for 2 months. I will suck my house battery dry if I run all of my accesories while running. i.e. stereo, ballast pumps, heater, heated seats, lights. I'll get a few hours. I ended up needing an additional charger when docked. But then realized my battery combiner was only charging sometimes. So I would reccomend at minimum a second battery. Playing the radio at a low level for 45 min while anchored and then having the boat not start never made my wife happy
.. Or me for that matter.