We have a roping gelding who tore a suspensory ligament and sustained some tendon damage as well. Before his injury, we used SMB 3's. But after, they just didnt give him the support he needed, so we bought the Iconoclast Rehab boots. They have been amazing. They did change his movement a slight amount, and they are a bit bulky, but without them, he would come up lame after a small amount of work.
We decided to buy some for our mare who never had an injury, and she seems to do ok with them. I like that they give more lift with the second strap. Especially for dainty thoroughbred legs.