POE To DC Or AC Extractors

What kind of experiences have you had if you have used devices that take POE power and provide (more commonly) 12VDC out. One example we've used is LifeSafetyPower's NPE-130, and it seems to have work well for powering analog cameras.

But has anyone tried really pushing these to their limits with other devices? Are you confident in using them or cautiously reserved?

We have used the Tycon POE splitters (OEM I belive is Laird Technologies). They have worked with old non POE IP cameras.