I've got a frame mount backhoe, with an 18 inch bucket, for my 23 HP diesel tractor with front end loader. I've found it to be extremely handy. It just takes a bit to get it on, and once I get it on, I hate to take it off because of that reason. Taking it off only takes about 5 minutes. It does a pretty reasonable job of digging.
However, I usually have a friend's Kubota excavator parked in the yard. It is certainly bigger and faster, but one of the things that makes an excavator so much faster than a backhoe is being able to move and reposition it without having to deal with outriggers. But, it is pretty limited to digging and leveling.
I only have casual acquaintance with the Teramites. But I'd have a hard time recommending one. Instead, I'd go with a factory frame-mount hydraulic backhoe on a conventional compact or utility tractor. The smaller termites had gas engines, and for something like this, I would only recommend a diesel. As far as I know, they make some 4WD versions, but I've never seen one. If you will be using a loader, you really want 4 WD. Also, as far as I know, none have PTOs or 3-point hitches.
Ken
