They did well the first few years, but then not as well. It was both the Yellowjackets and I think, to many hives in my area. Withing the flying radius of my bees are berry farms. they bring in 100s of hives and I noticed that as they have grown, my production went down.
In addition, we have a lot of backyard beekeepers around here so picking up swarms gets to be a real competitive sport
I have been around for a while so I get a lot of calls, but this year was skimpy for swarm pickup.