After having some bad experiences with SmartUPSs (the standard boiling battery issues endemic to many of the older products, and one that decided to fail hot... blowing fire out the vents on both sides), I swapped everything to Cyberpower and have been quite happy. I currently have:
1 3KVa online unit with add-on battery pack (server closet)
1 2.2KVa pure-sine (my office)
3 1.5KVa pure-sine (entertainment center, wife's office, sewing machines)
I've had one issue, where one simply went catatonic. Called Cyberpower, was outside of warranty but it was a known issue, they shipped me a brand new one and a prepaid shipping label to return the defective unit for recycling. Maybe 10 minutes on the phone. I was very impressed.