[Superfishman186]

I had one hooked up to my two group 31 agms for my terrova, with the amount of draw the terrova pulls the measly 10 amps that the charger puts back is kinda a waste, it would take me 3 days on the water to charge up the batts after just a few hours of use.
I thought it would be a good idea at first but it is just not enough charge to be noticeable and I commonly make 10-15 mile runs with the boat.
Also the ten amps that the charger is rated at is the maximum, that doesn't mean you will get that, based on the output of your alternator and the requirements of your engine you could only be getting a fraction of that to charge with.

It certainly doesn't eliminate having to charge the batteries when i get home, maybe just gives a small boost for a few extra minutes of trolling. I have since removed it from the boat and installed it under the hood of my truck and ran wire back to the hitch with a 4wire quick connect and charge the trolling motor batteries while hauling the boat. I suspect this works better because my truck has more charging amps to spare than the optimax does.