Not a bad idea, but I'm more concerned about the comfort (i.e.
vise-like pressure on my head) after about an hour or so. The gel seals
help a bit but I understand typical passive noise reduction headsets
are all pretty much the same as far as clamping pressure(?)

It depends on how wide your head is.
A narrow head does not feel as much clamping as a wide head does.
DC 20-10's have an adjustable head band and ear cups to fit wider heads.