I have two of the 2200 XR APC units with external 48vdc battery banks.

they run video/audio studio and work very will with the grid and off grid.

that model has built in cooling fans, and seems to work great. I don't
use my solar for charging the batteries except when the grid is gone.

if you get the XR units, they come with anderson power plugs for
setting up a larger battery bank.

I also have a 1200 watt 24 vdc unit I hacked an Anderson on and it
runs on a stack of xternal AGM's

they work great for what I do with them, but if I was going to have
fulltime inverter to AC setups going, I would probably buy a Xantrax
ProSine or a Xantrax SW2024