The difference is the xp1000 is alittle cheaper. Has the same output as the D1600 but has a thinner casing. If there mounted inside the vehicle I would run the XP1000 and save some money
one battery will be under the hood in the secondary tray, i have a D3400 there now and the D1600 is the same size so id probally put a D1600 up front, and a few XP1000 in the cab, would there be any problems with that?
No there wont be a problem, that sounds like a good idea. The D1600 would be the one for sure under the hood.