Does the vendor offer support/maintenance contracts?
the quality of the equipment. If you do have a UPS that does not output a sinusoidal waveform, some manufacturers strongly urge you to not put a surge protector between the UPS and the computer. The surge protector might mistake the non-sine waveform as a power surge and try to send it to ground. This could be bad for your UPS, not to mention your equipment. I don’t know if this has happened or not, but I wouldn’t chance it.