So far the 85w panel is doing great, and keeping up with our consumption when we are there. When I installed the system a month ago the batteries were at 12.7volts and the weather was cloudy so I never even got to see if the panel was working correctly before we left. After a weekend of use the batteries were at 12.4volts and the panel was only throwing 1amp into them.
The weekend after that the batteries were at 12.8 volts when we arrived. This was a dissappointment cause they had a week to charge, but after talking to my uncle who lives near my property, he said it was overcast for most of the week. It was raining the Sunday we left and once again the panel was only feeding 1 amp into the batteries which were at 12.4volts.
This past trip when I installed the LEDs and stuff in the trees we arrived and the batteries were at 12.9. But after a weekend of inconsistent sunshine, sucking about 80-130watts the entire Saturday playing music and charging my drill batteries while working, we left on Sunday in bright sunshine and the batteries were at 13.3 volts and still charging to the 13.5 limit the controller is set at. The sun angle was less than ideal as it was only 11am when we left, but the panel was feeding in 40 watts and 3amps into them.
I have yet to be at our property on a clear day and at optimal time for the sun angle to see what it indeed is putting out, but so far it seems to be working quite well, even in cloudy weather!