If you're worried about the charge rate on the batteries, check the voltages on them. If the batteries are on their way out, the alternator will work harder to bring them up to where they want to be.
Great deal! I'd love to get the bigger MEP 803A for my house. Waiting for a good deal to pop up like that close to me.
Good job getting that MOV & Quad mod taken care of. Easy & gives a piece of mind.
Trailer is very easy to change over to 12v so it will plug into your truck. I modified mine to pull level & with lights. I made a thread on it
here.
If you haven't already, give the unit a good load test. That will bring up any problems that may be there.