I have found very little difference between the two as far as traction/walkability goes. But that depends greatly upon what we are talking about. We obviously don't get as much snow as upstate New York, but I cannot imagine a situation where the type of heel makes any difference walking in deep, soft snow, such as the kind I am going to have to face momentarily--it all just sucks, and takes a lot of effort.
As far as hard packed snow, I am wondering why you would want to penetrate its surface, and particularly only with the heel. In such a situation, I would think the forefoot would not sink equally to the heel, much the same as walking on soft earth. I'd prefer to not sink at all if I can get away with it, even if the coefficient of friction on the surface is quite low. I can deal with that, within reason.
In any case, I won't be wearing any of that stuff when I go to clear out a portion of my driveway so my wife can go to work. It will be regular old flat snow boots. My job got called today, so I don't have to worry about much.