Upload & Sell: On
Unless you have a purpose for an older MFD back, I'd suggest the film route as well.
You're not getting anything special resolution wise compared to 24-36MP current sensors in DSLRs. And while you do get a larger sensor, it's still not that large.
If I wanted a bigger "sensor," liked MF, and couldn't afford a newer, big-resolution digital back... I'd get a Mamiya 7 or 7II. You'll have to suffice with a rangefinder, but you'll get a massive 6 x 7 film size, world-class lenses, and a very compact camera.
If I had time to deal with film, that'd be my choice.