:: Belkin Regulator Pro 650VA and APC Battery Backup 500VA
Conclusion
Congratulations to both companies on fabulous products. Both UPS systems work great, although there are some differences. By checking out the APC site, the highest USB UPS they offer is the 500VA, which to some could not be enough. Another difference is that Belkin's software has a lot more features then APC. While Belkin offers a full suite of software, APC just gives you the bare necessities. With the Belkin 650VA you are given one extra outlet then with the APC 500VA. The APC offers a surge protection of up to 360 joules while Belkin only offers up to 150 joules. Both offer Unlimited Connection Guarantees on their UPS systems.
If your one of those people that like to have control over your hardware, and have the money, I would probably recommend going with the Belkin because of it's suite of features and extra outlet. But if you are just looking for something to protect your system, the APC 500VA will do a great job and is cheaper.