Short, fat, and heavy, Tripp Lite’s SMART1500SLT attempts to overcome the price barriers of its APC rival through selective reductions in features. Customers retain enterprise-class features like a hot-swap battery tray and pure sine wave output, but lose the convenient LED front-panel display.

Also gone is the load shedding feature, which Tripp Lite addresses through separately-purchased power bars. All eight outlets belong to a single power group.
The SMART1500SLT’s simplified design also means that more users will want to use its included software suite, which can be accessed by either USB or nine-pin serial connections.

Tripp Lite includes documentation, USB and legacy serial cables, and a software CD in its SMART1500SLT support kit.
- Power Protection Or Rage Prevention?
- Why So Pricey?
- APC Smart-UPS SMT1500
- SMT1500 Management Software
- CyberPower CP1500PFCLCD
- CP1500PFCLCD Management Software
- Opti-UPS Durable Series DS1500B
- DS1500B Management Software
- Tripp Lite SmartPro SMART1500SLT
- SMART1500SLT Management Software
- Test Settings
- Benchmark Results
- Conclusion

Would recommend it although they might be a bit costly but they perform really well.
You've also made me want to test my non-pfc ups with my 850hx, but my gaming rig and my workstation are an hour apart....
wrong
No it's not wrong, a small UPS equipped with a bunch of low-cost standard deep cycle SMF/gel-cell batteries is a lot cheaper than a big UPS that comes factory equipped with that capacity. APC's Smart-UPS units come with ~2700 VAh and their price tags start at about $8000. Sure they are also able to provide up to 40 kW power from the batteries but this is far more than needed for home use.
The problems that may arise is that the inverter circuit may be too weak to operate for longer durations which is a problem among low-budget UPSes. It may not be able to run equipment for hours since its intended use to deliver power from batteries lies within a time-span of maximum half an hour. A sign to look for is if the UPS has cooling fans. Those that don't have that are probably not constructed for longer durations.
Another problem is that many of these UPSes are equipped with circuitry that monitor the health of the batteries. If you swap the original batteries with batteries that have higher capacity they will need more time to recharge and the circuitry may misinterpret this as that the batteries are "dead" since they don't take the charge at the same rate as is expected from smaller batteries.
The recharge voltage of the recharger circuit may not match the recommended voltage of the standard batteries if you use cheaper open-cell batteries. I've been told that the electrolyte of open-cell batteries tend to evaporate over time if you feed them with a higher than recommended recharge voltage. The solution to this is to make sure that the ventilation is good and keep refilling the cells with distilled water. Sealed gel-cell batteries should have the same recommended recharge voltages as those lead batteries that are used in the UPSes.
The solution to the last two issues could be to put on an additional (smart) recharger on the batteries that is connected to them 24/7 and let the battery/recharger circuit sit behind a rectifier just to be on the safe-side. This may of course confuse the battery health monitor circuitry of the UPS making it think that something is wrong with the batteries. If I had the budget I would definitely try these things out.
I looked at them and if you want 120V power, they are good but if you want 230V then there is a problem. The models that provide 230V and are not crazily big (6 kW is far beyond household needs ...) use 12V as input. It's much better to use 48V or at least 24V as these setups with serially connected batteries can use thinner wiring. But this is an interesting option indeed since they come with an automatic utility power pass-through switch and a recharger.
In a word, "wrong" was the right answer. Ignoring everything else, for the simple reason that charge management isn't where it needs to be; you will destroy the UPS trying to charge and float anything behind 2x or 3x the normal capacity. There are vendors (apc is one of them at the entry level position in the market) that offer expandable runtime UPS solutions; if you are going to be relying on your backup and not just using it as a hobby project (there is nothing wrong with that) you are going to need a properly engineered solution.
I'd like to see Tom's test an old square-wave UPS, see if they can actually trigger an Active-PFC PSU shutdown on a swap to battery power. I'm guessing it won't have anything to do with the waveform coming out of the UPS.
And before you come back at me, I have a degree in Electrical Engineering, I actually have an educated basis for my beliefs.