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To be honest, with digital, I don't quite see the point of medium format. ...
What format is approriate for what use has changed several times over the nearly two centuries of photography. The most recent sea change has moved everything down one format.
The APS-C and similar "crop format" sensors are roughly the size of the old 35mm single-frame, or "half frame", format but exceed the quality of 35mm double-frame, or "full frame", film cameras.
Today's crop of "full frame" sensor DSLRs have sensors that match the size of 35mm double-frame but deliver image quality that requires at least the better range of medium format film cameras. These cameras, in many ways, are the "new medium format".
The so called "medium format" digital cameras, DSLRs like the Hasselblad H series and the Phase One backs used on technical cameras, have image sensors a bit smaller than the 645 film format but function as replacements for large format film. The performance of the Kodak sensors in these devices, including their own Leaf brand products that were recently acquired by Phase One, is beyond that of medium format film and easily in the class of "large format" film. They are, in effect, the "new large format" cameras.
My point is that there is a point to medium format today; it has the same use as large format had yesteryear (OK, I'm an oldster and grew up watching the Saturday morning westerns on TV in the '50s...).