Join Date: Apr 2006
Thanked 170 Times in 167 Posts
Rep Power: 12
If they JUST change to AGMs, and don't change the charging, they'll be throwing good money after bad. AGMs are just as easily damaged by overcharging, and you can't "fix" them by just topping up the water. Proper charing protocols and matched voltage for the AGMs are necessary in order to get the performance from them.
The good news is that AGMs don't self-discharge as fast as wet cells, they can be left without a charger for a month or two at a clip and take nearly no damage from that. Even six months at a time, if you believe the makers.