[edit - I lost some of this post and am fixing it before reading Jerome's response]
Have they improved? Last time I checked the UPS couldn't handle a single Mac with two hard drives.
That aside - and I'm not trying to sneer at Jerome's set-up again, because I'm willing to be convinced othewise - my argument has always been that if I'm working at the machine, I save subconciously every single time I do something I don't want to lose out of habit, so the APC shouldn't be necessary; and if I'm away from the machine, I've already saved anything I want.
But I do have my computers on two (or three) reasonably good power strips in series, and my audio equipoment is plugged into a fused isolation transformer box.