Well, HfH is kinda singlecoilish sounding, but not exactly of course. Still its closer than most of humbuckers. I'm using HfH with 250K absolutely fine. That 250k vs 500k is a bit overhyped thing IMHO.
But for sure, coil-cuts (i.e. using just one coil of humbucker) or parallel connection of coils are much better with 250K volume pot - thats for sure.
Anyway, full humbucker mode loses very little by using 250K volume, but single-coil of humbucker or humbucker in parallel gains a lot.