I have a 450w APC UPS, maybe two-three years old. Brand new I pulled the little joke of a gel-cel out of it and wired it to a marine battery. After maybe a year the marine battery went bad, so I went to the Interstate battery wholesaler and grabbed another "blem" marine (deep discharge style) battery. It's a big one, putting out around 900 cca. Well, here it is a year later and it's bad. I just now put it on a "smart" charger which said it was 11% charged. I'm condition-charging it now and it may come back to life, but I wonder... is the APC UPS incompatible with lead-acid batteries? Or maybe I'm screwing myself buying 'blem' batteries? (i've had excellent success with them in auto use) EDIT: Also, maybe someone could recommend a better UPS on a budget? Something I could snap up used off Ebay maybe?