TNT,
The ditchwitch guy says they've been out for 10 years. I'm planning to demo their 500 and the MT 52, though it's a little hard to tell how they'll work, seeing as nobody around here has an overhead grapple attachment for their machine. I figure I can use the bucket-like grapples they offer, to get a sense for capacity and how they travel with a load.
We'll put up with the extra maintenance with tracks, figure the least I can do is not compact my customers' soil. We'll use plywood or mats to avoid damage at pivot points on lawns.
We've got tons and tons of backyard cottonwood to move in the next month or so, so I'm eager to get one.
Thanks for the info.