I've had a couple people tell me how effective these ultrasonic things are that plug into an outlet, at keeping out spiders and such from their homes. One of these people owns a bearded dragon which doesn't seem to be bothered by the device. But both people said, and cursory research confirms, that these can bother pet gerbils, rabbits, and such. Do any herp keepers here use ultrasonic pest repellent, or have experience with them? If so, can you recommend a brand? It occurs to me if these work so well and are safe for herps, they could help with mite prevention also.