One thing I find good about them, which is why I'm planning to let this one do its thing, and take over. They really get busy, once they've taken over, they clean up, and build-up very rapidly. If there are any frames that, as yet, have no combs, they often build in that empty space, very quickly, but often very poorly, comb that can twist and turn in every different direction. So, if I want them to accomplish what they're best at - building up a colony. I need to make sure that all the frames have good, straight, combs in them, and there are no empty spaces in their new quarters.
After they have built up the nuc, and filled all of it's combs with honey, pollen, and brood. It's then time to break them up, after killing their queen. Then give no receiving colony any more than one of the frames of brood. Usually, the bees that are reared by these colonies, can exhibit many undesirable traits, but if they're the minority, it usually isn't too bad. They are very industrious, usually more so than other colonies, and make good assets to colonies that have some in their populations.
They are difficult to requeen. But, when dividing them to divvy out their resources, if you kill their queen, shake the bees from the combs and leave their old nuc box there, but empty and without a cover, before giving the combs to weaker colonies, the brood usually doesn't cause much of a problem for stronger hives and nucs that receive it. The now orphan bees, will soon take up residence in nearby queenright colonies that accept them. This is a good use for them, because it is almost impossible to requeen them, they will usually not accept any non-AHB queen, even a virgin from a queen cell. The only way I've reliably requeened them is to remove their queen and all field bees, and introduce the EHB queen via wire cage over emerging brood and the nurse/house bees that remain.
I know the Tucson Bee Lab, has this problem on their To-Do list, but I'm not sure when they'll be working on it, or if they'll find a solution.