I bought 60 the first year and installed two in each of my three hives. I placed them in frame space #1 and 10, it them forever to start to use them very much. I still have 54 in storeage/never used.
I find I have better results in mite control by removing the queen and three or four frames from the built up hive and making a nuc, this break in brood cycle puts a pretty good dent in the mite population, plus it tends to help control alot of swarming.
Have thought about taking the new ones I have and putting them in a deep and try it as a honey super,with the larger drone cell dimples formed in the plastic foundation if it works and they draw the larger cells for honey it might be kinda fun. Jim
My two cents- I'd put one drone frame per 10-frame brood box. Late Spring (swarm season) is the big drone-producing time. By late summer bees make much fewer drones.
I use them only for drone culling to help cut down on mites. Your queens don't mate with their own hive's drones. I've been taught that the virgin queen takes a mating flight to a drone concentration area and usually mate with a dozen or more drones from various other nearby areas.