What I've heard about predator mites is that they will never fully exterminate the pest...
Having said that, i am pretty sure I got predator mites with some of my store bought violets, and I haven't seen any other bugs, so I guess they do work...

Karin

I think they probably die off pretty easily, unless they have constant food. That would not be the case with most of our violets. For me its a matter of security. I just got started in AVs again after many years, so I have brought plants in from two different eBay vendors. I do have a few plants that look funky, but I can't see anything with my 40x loupe magnifier. I think it is cultural, mostly the potting mix I was using is to blame I believe. I now have my potting mix down and also my water techniques down. I just want to eliminate the potential of any nasties plaguing my plants.

A coworker released 100 ladybugs all over her many many plants here in the office. Though she still struggles to eradicate pests completely, the plants that benefited most from this experiment was her three giant AVs. They were riddled with these little white things ... as in, completely coated with them, and a year later, they've recovered 100%. All green and flowering again. I would never have believed they'd bounce back if I didn't see it with my own eyes.

(And yes, a year later, we still find ladybugs here and there.)

Danielle, were they regular ladybugs or a different than we usually see? There is a type of ladybug that you can get from this same place, I can't remember now what they eat.

Keep in mind (assuming you plan on releasing them indoors) that:
*They will wind up everywhere in your home, as opposed to staying right on the plants.
*Your indoor conditions may prove detrimental to the mites. (For example, one of the main reasons spidermites are such an issue indoors for many people, is that those organisms which prey upon them -- including other mite species -- typically cannot survive for long in the arid environment commonly found indoors.) Should this be the case, then purchasing the predatory mites, may prove a waste of $.

I don't have experience with predatory bugs on my indoor plants, but we did use them in our yard for an incredible flea infestation. We moved into a house in late winter (February) and by April we couldn't walk outside without our feet and lower legs being speckled generously with fleas - it was icky on a level all it's own. We had pets and I was in the practice of systemically spot treating them, so I know they were not the source of the pestilence. I got some dry mix from the pet store "Beneficial Nematodes" which was mixed with water from the garden hose and sprayed around on the ground. It was like a miracle - within weeks, we had no more fleas at all. None. We lived in that place for ten years and never again had a problem. I even stopped treating my pets because we didn't have fleas in the yard - it was great!

That's what the guy whom I spoke with said. The ones that kills the fleas are very effective.