The single point meters or cigarette plug in kind are pretty much useless - Except they will tell you if things are wrong right now.
They cannot tell you if a bank is fully recovered unless you are willing to let it sit for an hour. They can tell you after it is too late that the bank has been discharged past its usable capacity.
No, go get a good one:
Bogart EngineeringVictron XantrexThis is just three, there are others. If it is less than 200$us, it probably is not going to do you any good.
I put in lots of these things before the depression and finally got one in my own coach (because a client didn't buy it) and I wish I had bothered sooner.
Matt
