What a sweet attachment! And that mini BobCat is the ticket for less destructive tree clean up and disposal. That machine saves you thousands of man hours and your own body from unnecessary back breaking labor. Plus your guys will be happier and not move to other professions as quickly.
My boss has a similar setup for his avant. Except you use the grapple to hold the brush. It's very similar but seems easier since you don't have to change implements.