Capt. Insane:Along the lines of this (as I'm sure the OP may eventually be interested), what would be a good brand to go with? I need at least a 1000w back up (computer draws 750w).
A 1000 watt unit should work OK if you have included your monitor in this figure. Remember you need to include everything you would need if you lost power. I have a 5w night light hooked up to my system...would need it if the lost power was at night. SO..check the run time and if you are happy with it, then go with a 1000 watt unit. If you would like more run time then go with a larger unit. That would only be the difference for you in a 1000 watt and a larger one.
Selecting a brand name is a like selecting a computer. There are several very good brands you could buy.
There are two major types of battery backups. The ones that give you a chopped wave form and the ones that give you a true AC waveform.
The ones with a true AC waveform will cost you a little more. They will be the best because they will give you a true 50hz or 60 hz waveform to match the ac power you are using. If you have equipment hooked up to the the battery backup that has an AC transformer, you need this one. A chopped ac wave form is hard on a transformer sometimes causing damage to the transformer.
I have used APC for several years. Right now I am using an APC Smart-UPS 1000 (True AC waveform). I like this model because if your power is too high or low, it will self adjust without using the battery most of the time. You can swap out the battery yourself without having the factory do it, even swap it out while it is on if you need too. This is not true for all APC models, nor true with all brands.
BUT, again, I would say search and find what you need in a good unit. If it is a good brand name, you will have a good unit no matter who made it. Will my next unit be a APC? It will depend at that time who has the unit that best fits my needs....and so should you.