After manipulating the files in various programs and experimenting to see which methods and programs (ie. shadows, fill light, exposure adjusts, curves, NR, etc), I've found where I personally would consider the maximum usable DR for each camera/back. I simply tried to find the best shadow lift combination where the noise reduction could still control the noise level enough to make a satisfactory print. I looked at the wedge and recorded the darkest discernible level and converted to stops. Probably Imatest would do much much better at quantifying these data, and even then I suspect that many of you out there are working with different definitions of DR, so for the sake of argument (or rather to avoid arguing) I'll call these numbers Eric's usable DR figures or EDR. I find looking at what will be usable in print a much more useful number than a manufacturers spec or a number from DXO but YMMV. Note that this does not really take in account for the differences in pixel count. Also worth noting the first aptus 12 I had for testing seemed to perform a bit better.
Canon 26 steps = 8.7 stops EDR
Hasselblad CFii-39 in single shot 33 steps = 11 stops EDR
Hasselblad CFii-39 in multi-shot 35 steps = 11.7 stops EDR
Leaf Aptus 12 32 steps = 10.7 stops EDR
Phase p20 (non plus) 29 steps = 9.7 stops EDR