Cyberpower, APC, Liteon pick one.  All current models are compatible.

So are you both saying that power delivery type isn't relevant? The research i've done says that some power supplies will not work simulated/stepped/approximated PSU.
 

I have a 1200 P2 connected to a CyberPower CP1500PFCLCD, and it's been a very reliable unit.
 
http://www.cyberpowersyst...ew&imageI=#tab-box
 
I've actually used it for over three years now, and I've even gone so far as to add three more of them to power my home theater and network components. I was originally using it with a Corsair AX1200, and it replaced an APC SUA750 when I discovered that that one didn't have enough overhead to comfortably power two GTX 570s in SLI.
 
The only downside I've found is that the display (when showing the power draw, in wattage) acts a little wonky when it's paired up with the EVGA power supply and the PC is sitting idle. Not sure if the display is accurate or not-- the wattage jumps all over the place, which it didn't do with the Corsair-- but it doesn't seem to affect anything, and it shows a normal reading when the PC is under full load. Leaving the display off makes it a non-issue, unless you're completely OCD about these sorts of things. Everything's documented here, if you feel like poring over it:
 
http://forums.evga.com/1200-P2-Erratic-power-draw-m2330929.aspx
 
So far it's had no trouble keeping the PC running when the power has dipped, surged, or dropped out completely. The batteries have held up well, too (unlike the batteries in the APC unit). I've never used the included software, though, if that matters. I just use the power settings in the Windows control panel, but I've honestly never had the power go out when I wasn't at home and had to rely on the PC shutting itself down when the battery got low.