My top mount recommendation right now if someone is starting from the beginning is the PhaseOne DF/Mamiya Mount.
It can attach to your tech cam via common adapter plate, it can also work on both the Phase One AF/DF bodies and also on the Mamiya RZ II Pro systems.
It can also be adapted to other systems. This is our most popular selling Mount.
If you are considering the Leaf Platform then you have some interesting options as well.
First you could go with the Leaf Aptus II 12R or 10R. These two models utilize the Hasselblad V- mount , but offer a unique feature. Their sensors rotated internally so you do not take your back off and physically rotate it.
Secondly, Leaf still offers their Afi mount. This mount allows the digital back to attach to the Afi/Hy6 medium format platform. Most technical cameras support this mount as well. The unique feature of this back is that the screen tilts for better viewing angles.
Hope this helps.
Lance