I got a package of the regular Dynamite vitamins when I brought home a horse on trial (that was what she was already getting and I wanted to keep her diet the same). It was a pain to get a hold of since I didn't know a salesperson and you HAVE to enter a rep's name even when you order online. When I finally got in contact with a rep, I was surprised to find that they didn't stock any locally and ordering online was the ONLY way to get it.
I ended up returning the horse I had bought it for, so I held on the remaining vitamins until I finally did buy a horse. He was underweight and hadn't been getting very nutritious feed, so I figured the Dynamite would help. One of his biggest problems was that the previous owner had been trimming his feet himself... badly. For the months my horse was on Dynamite his feet barely grew at all, which didn't help in the effort to rehab them. I ended up switching to a ration balancer (Triple Crown 30% Supplement) and the growth rate of his feet took off within a couple weeks.
I later got a subscription to FeedXL.com and found that Dynamite was missing a lot of key nutrients necessary for hoof growth (copper, zinc, etc.) I guess you have to also feed Dyna-Hoof to get a balanced diet from them. I didn't try feeding both Dyna-Hoof and Dynamite, since by then I was already getting very good results from TC30, and TC30 is cheaper than feeding both of those supplements together.