If you are trying to make sure your calf stays sound there is no substitute for letting them act like their counterparts in the pasture and turn them out into as big an area as possible to get exercise. Cattle need to walk. In my opinion, a signficant portion (certainly not all) of the "structure" problems with show cattle are a result of them being fastened up in too small of a stall, on very hard ground, with little exercise.
In addition to the feed we have mixed, we do feed an extra mineral supplement + Show bloom. Does it really do any good? Probably not.
Agribusiness is highly sophisticated and puts billions into research. When you look into buying a supplement, look up information on who developed and who sells it. If it is a product that is supposed to "fix" someting and it wasn't developed by a really big company or someone who has real scientific research experience, you are probably buying snake oil. Someone just doesn't mix up something and it work. Someone can just mix up something and sell it. Most of these products are not regulated by the FDA or anyone else.
Things like Optaflexx and Revalor were developed by very big businesses and are used by very big businesses.