It's a big step forward in my opinion; I'm doing mostly studio still life, and the occassional landscape and people shots , all with an Aptus 75, on Sinar and sometimes the Mamiya RZ.
I'm also using the 5DII as a backup and walk-around camera.
The ratio of 3:4 is something that makes the new back a lot more useful for me than the current Leaf backs ; 80 MP are great, I can never have too much resolution, and the clients will love it.
Sure I would rather see an even bigger sensor, yet there is a reason why we don't see those, I guess.
A multi-shot back would be too limiting for me, that's out of the question; with that kind of investment, I want to be flexible.
It remains to be seen how moire is being treated by the Aptus 12 - it's a big issue with the A75 - and image quality in general, in particular when camera movements and/or wide angle lenses are being used on a view camera.
But I'm optimistic, given Leaf's experience and excellent track record.
Good to see the R-version as an option, and the much more affordable non-R model .
It's a great offering by Leaf from my point of view, the A12 looks very tempting to me, finally a real upgrade possibilty for my trusty old A75 .
What I'm missing is Live-View - is it not available at all anymore ?
Also, is the longest exposure time still 30 seconds ?