As I have limited experience, I'm not the best source for backhoe feedback, but that said, here's what I have found:
The breakaway capacity is impressive....rocks, stumps offer little challange if the bucket curl leverage is applied right, but it has taken me a while to grasp technique. I have yet to dig down a full eight feet, but have no doubt it does that....you would however, essentially be digging below your feet, so my guess is it would require a lot of leaning forward to see what was up.
The limitation I find thus far is with the swing factor..(60 degree I think). If you are just digging a hole you plan to refill, it is not a problem, but if you want to move material, a lot of tractor re-positioning is required. My workaround is to load the mule and move to dump. A wider swing would not be a huge improvement, so I'm probably being overly critical. All in all I'm quite pleased to have it and have a list of projects lined up for it.