For what it's worth I am in Zone 7B North Carolina about 30 miles from Charlotte.
I am taking a season off to prepare, so I have no colonies at present.
I am abandoning vertical hives. But still have boxes, supers, and frames for Langstroth deep, medium and shallow. And I have a 2 frame extractor.
I am not opposed to selling off stuff, including the extractor. Nothing is "precious".
I plan on trapping and catching bees as opposed to buying nuc's and such.
I build all my own equipment, at least the woodenware.
I have just read through the two books that Dr. Leo pushes, but I have never gotten an email response to my questions from him so I have no access to an "expert."
So my thoughts are on depth vs breadth. I seem to see that in colder climates probably above my zone by a significant distance, the Lazutin or Double Deep Langstroth do well at a 14-20 frame width. I like the idea of the Layens in that width as well. But a single height deep at 25-40 seems possible. Initially I was concerned with lateral movement of the cluster during wintering.
So what's going to be my best bet? I realize that there should be opinions involved. I accept that and realize there is no definitive answer, except for someone with motivation to sell books or speaking engagements or equipment. But I am interested in hearing those opinions an don't need disclaimers to go with them