So who has one and which do you have? Why did you select the one you have?

I'm going to add one finally to the boat. After researching I see 4,5,6,10 amps per bank chargers and now i'm at a loss more or less. I've noticed most use the ProMariner ProSport 20 whether 2 or 3 bank, but do you really need 10 amps per batt to charge?

David chime in on this one if you could as well.