I don't care how "legitimate" the source, part of my QT process is putting the new arrival into an enclosure that was pre-treated with permethrin-based mite spray the day before the new one arrived.
I have the best quarantine I can in my small house and I believe I have it limited to just the new 3 ....knock on wood. I have provet a mint on the way and I'm treating the whole collection just to be on the safe side.