Why you shouldn't buy cheap UPS
 

Well, just had a very bad experience with one certain UPS I have. Maker or brand is Goldenshield, it started shutting itself off only when running a computer and monitor which had been its usual load for 2 years.

In the end I was forced to plug computer directly into the wall outlet and just have monitor feed itself from UPS. This defeats the point of UPS...

So yes, in retrospect I probably should have stuck with APC (I have a 6 year old APC which works fine) or another well known maker.