RIGGSJR,
The frame mounted will work well, but limit the options such as a MMM in conjunction with a BH subframe. Although most will not do heavy BH work with a MMM attached it is a drawback with the subframe setup.
Also, the R&R of the 3PTH is a bit more difficult. You may want to check out the new Bradco 3375 that has a 4 Point connection that is similar to the Kubota TLB 4 Point saddle connection. The Bradco setup is a subframe that bolts onto the rear casting, then ties into the tractor frame midpoint under the tractor.
This setup does not reduce the ground clearance of the tractor, and is more compact, sitting closer to the tractor which reduces the overhang and O/A length of the unit.
Carl