I tested the auger attachment, and it worked VERY well. Their digging capacity leaves quite a bit to be desired, but they will probably dig more in an hour than two men. I rented one once for using in snow removal, but that didn't work so well.
I would like to have one, but when I checked out prices, horsepower, lift capacity, etc, I felt that they came up short. They seem much better suited for landscapers than for tree service, which is what I was targeting it for.
They just cost too much per usage of the machine.
For example: they only pick up logs to around 5' height. That isn't enough to get any wood onto my single axle dump trucks, and certainly won't pile them up onto the middle of the truck.
They only have a lift capacity of around 500 lbs. That is MUCH more than a couple of guys can carry, but for somewhere close to $15 grand, they are a complete joke compared to the 6000 lb tipping capacity of my A300 bobcat for a measly 50 grand. And being skid steer, they will do WAY more turf damage than either a log dolly or my A300.
It was an easy call for me, but I am sure other tree guys will put them to excellent use. For example, I'll be they are great for moving a big pile of wood from back yard to front so that a grapple truck can finish the pile.