swinn585,
I have a bush hog 2103 post hole digger. I think that it is the largest model they make, but I am not sure if it is the "industrial" model you are referring to. Mine does not have the hydraulic downforce kit you are referring to, but it was an option when I bought it. I have only dug a few holes with it so far, but it seems pretty well put together. I am going to be putting in about 400 fence posts with it in the next month or two, so I should have more info then. I think that it is also their only model with a slip clutch, as the smallest one has a shear pin, the medium one has a shear bolt, and the largest one has a clutch, again if my memory serves me. One thing to consider is getting the optional stands for the PHD. This is one heavy sucker to get mounted to the TPH, and having the stands would likely make it easier (I did not get them, but am thinking of making some of my own.)
The price of mine was around $1000 with a 9" auger, but I do not remember how much the downforce kit added.