I have a number of power outages, as something in my house wiring trips the main earth leakage trip periodically, so a UPS seemed to be a good purchase.
The unit was easy to set-up and connect, as the internal battery was already connected (different to what the manual says).
When simulating a mains failure with just 1 PC connected, the unit lasted 30 minutes before initiating a shutdown of windows. With all my other peripherals connected (second PC, scanner, wireless router, laser printer and inkjet printer) the load got up to 50%.
Three points to note (hence the 4 stars):
1) The software lacked readable documentation (well English anyway), and it took a few installs to get the PC to see the UPS. The software is an overkill for 1 PC, and is really designed to control many PC's over a network, so it has agents/services that must all work correctly for the software to monitor.
2) The unit comes with two short male to female IEC cables. Fine for connecting two PC's only. So I had to purchase a separate rewireable IEC male plug and wire it to a multi-way extension socket to power my other peripherals.
3) The unit still runs warm even when nothing connected to the UPS is powered up, so not too good for ones electricity bill I guess.