I have never bought the T&D bolt-on High Riser set. When I started doing them here, I milled them with that turn-down so there is more material for the end supports. At some point, someone asked them to do a "custom" set........they gave it a part number. The set they sell is milled off flat. It probably will work fine, but I prefer more material on the ends, so I make my own from the MR set. I also prefer the bushings. I also have ratios and offsets that I prefer. They make mine in lots for me, with options not available in one-off orders. I can sell a person any of their stuff, at the same prices they do.....but I can also sell you things they make for me that they won't normally do.......often for the same money as their regular stuff. In the case of the High Riser, they cost more my way because I have milling time plus the cost of the Bushings. I have discussed with them the idea of them copying my end supports and machining all of the High Riser stands during there process. It would lower the price for my customers and also save me the time. I really don't make much on the modification. I just do it to serve my customers.
To answer the question of whether anyone has run them.....all of the Stock Eliminator High Risers I work on are using them. Seven years plus on a few that get run ALOT. No failures ever with 500+ over the nose pressure. The T&D stuff is VERY good. I think 600 open is my personal limit on a system that is held by four 3/8 bolts. Past that, I use the paired shaft, heavier duty stuff. I also modify those for High Risers and mill the heads for those if a person wants to do that. It requires longer valves, and some creative milling to get the geometry nice on a High Riser, but the stuff is bulletproof if done right.