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Although I'm heavilly invested in Hasselblad XCD system now it is very interesting to see the range of 645 lenses that Pentax currently offer!
Hasselblad do have the 21mm that is far wider but Pentax offer longer focal length lenses. I'm not aware of any announcements from Hasselblad for any long telephotos at the moment and the current H series are too big and heavy.
I bought a 907X and s/hand X1D & 553ELX and am supplementing my lens range with old V series lenses (where there is no similar focal length in the XCD range). Not that this is a bad thing but it would have been great to buy new telephoto lenses instead.
N.B. I am only interested in leaf shutter lenses so won't use adapted lenses from other brands.