If you thought of a choice of medium camera, there is an option with Mamiya 645 one of the most attractive (if you already “outgrew” the Soviet cameras). Partly because Mamiya belongs to the PhaseOne companies, being at the moment the leader of the medium format market making independently digital backs and permanently arranging favorable trade-in (an old back on account of new). You can always to pick up a digital back of the same PhaseOne or Leaf to plus to your Mamiya.
And today you can quite get the film medium camera Mamiya of the previous generation ( Mamiya ceased to support film backs from the DF index) and to film it or shoot on Polaroid. The price is much more available, than Hasselblad (which has the minuses), Contax, Rollei or the same PhaseOne.

Differences of the Mamiya 645
Mamiya 645AF

6450af
It was made: 1999.
There are no user functions.
It isn’t compatible to lenses of a D and LS series (the central lock).
It is restricted to digital backs (requires up-dating of a firmware).
Supports backs: LightPhase, H5 and H10 (6 MP).
It isn’t compatible to new digital backs of PhaseOne and Leaf.
Supports film backs.

Mamiya 645AFD

Mamiya 645AFD
It was made: 2001.
It isn’t compatible to lenses of a D and LS series (the central lock).
There are no user functions.
Exposure correction only on ½ EV
Restrictedly supports backs: LightPhase, H5 and H10 (6 MP). And also backs of P and P + on announcement of PhaseOne.
It isn’t compatible to new digital backs of PhaseOne and Leaf.
Supports film backs.

Mamiya 645AFD II

mamiya_645_afd_ii
It was made: 2005.
It is compatible to D lenses, but it isn’t compatible to the LS lenses (the central lock).
The user functions are supported.
Correction of exposure on 1/3 EV it (is improved)
Supports film backs.

Mamiya 645AFD III (Phase One 645AF)

1
It was made: 2008.
It is compatible with all digital backs of PhaseOne (P, P+) and Leaf.
It is restricted to LS series lenses (the central lock).
The user functions are supported.
Also it is on sale as PhaseOne 645AF. It is cheaper with the Mamiya logo .
Supports film backs.
notes:
P40 +, P65 + and all backs of IQ requires a firmware 1.5 on Mamiya AFDIII/Phase One AF
IQ backs aren’t supported after a firmware 5.10
Backs of Credo aren’t supported after a firmware 2.01

Mamiya 645DF (Phase One 645DF)

Mamiya645DF
It was made: 2009 — 2012.
It is compatible to all digital backs of PhaseOne and Leaf.
It is compatible to LS series lenses (the central lock).
The user functions are supported.
Doesn’t support film backs.

Mamiya 645DF+

Mamiya 645DF+
It was made: 2012
Focusing is better, than at the DF model. More capacious accumulator (Li-ion), 10 000 pictures from one charge.
It is compatible to all digital backs of PhaseOne and Leaf.
It is compatible to LS series lenses (the central lock).
The user functions are supported.
Doesn’t support film backs.
Camera power supply: own Li-ion battery, NiCd or NiMH battery or alkaline finger-type batteries. Don’t forget to make switching on the appropriate type of the battery in the menu.