Look at the ingredients and calcium content for comparison to figure it out. One thing for sure: nothing, no supplement replaces daily intake of good, diverse diet
I've never heard of a pelleted vitamin for tortoises. If there is one it is not a replacement for calcium supplementation. Like Yvonne said, these are two different things. Its not one or the other.
I use Vionate, which has calcium and D3, but I still use more calcium.
It is false that 'stones' are calcium carbonate built up in the bladder or kidneys. You can offer calcium in many ways aside from any other nutrient powder/ground pill you may use. Cuttle bone (a cuttle fish bone that is cleaned) or even pure Tums (not the ones with all the extra stuff) work too.
That way, with the cuttle bone or Tums the tortoise can ingest calcium as they see fit to do. ZooMed also makes calcium supplement blocks that some tortoises seem to like, other don't.
Calcium Carbonate is the best form of calcium to supplement with in term of being readily absorbed.