Jason,
I did the battery replacement thing too with an inferior charger. I eventually got a Xantex unit and it runs the batteries automatically through a program that keeps them in tip top shape. I can not recommend this unit too highly. The automotive units are okay for bumping up a battery now and then, but the Xantex unit is hooked to the batteries all the time. The entire time we are on shore power, the unit is computer controlled and monitoring the battery charge. Get one of these, you will not regret it.
http://www.network54.com/Forum/424840/message/1127389120
Regards,
Paul