Well, darn. Looks like one of those rare times where no one else has anything to say. We just put a half of a pallet of them on to give them a try, so here is what I know so far.
The dosage is way too strong. We put two strips on strong doubles, in temps in the mid '60's and one strip on doubles with one box of bees, more or less. The queens shut down for five days at least. Some longer than that. We went out today to split some of them and found that most of them had a bunch of five day old larva (or younger) but next to no sealed brood. (it was ten days after treatment) That tells me the fa killed all of the open brood that was there when the maqs were put on. On top of that we lost around 20% of the queens. The good part is that once the queens started up again they were on a terror. Expanding the brood nest like I have not seen since the good old day. But it now looks like we are going to have to put off splitting for another week to get enough brood to get good splits.
So, would I use them on singles. Yes. IF the temp is right, and IF you cut down on the dose. If your mite counts are low I would try a few just using 1/2 of one strip per single. The max I would use would be one strip per very strong single. (these things have a lot of formic acid in them)
Good luck.