Hey there, new beek here and I use them in both my hives, I run with double brood chambers.
Initially, the bees drew the foundation out and filled it with honey, like any other frame ... so that had me concerned. I have them placed in position #4. Shortly afterwards, I noticed the one in the bottom brood chamber were now full of brood, at this point I was inspecting my hives every week, so I knew when that brood occurred. I pulled them after 21days, froze them for two days and then reinstalled them. I dropped the drone frames that were in the top chamber into the emply slot in the bottom and will basically rotate those frames in that manner. After frozen, I did inspect the brood but found no mites! If one does the count should be very low given that these were new nucs and would have been treated prior to me getting them. I also use screened bottom boards as well ... I don't want to regularly treat with chemicals for mites, and don't seen the need using this intergrated pest management tools). Just ensure you pull your frames around day 21, if not you just increased your mite load!