A few weeks ago I bought Rebutia canigueralii (or Sulcorebutia rauschii). And now I've the problem - it is grafted on some cactus. In general, I prefer cacti growing directly on the soil. The seller said that it is imposible.
Maybe someone has anther point of view or has some experience growing this species.
That's a tough call. It would certainly need enough chlorophyl to grow on it's own. Any chance to share a pic would be great! But if not, I would apply the "better safe than sorry" rule here.
All Cacti are succulents, but not all succulents are Cacti
The Sulcorebutia rauschii I saw all had different colours, from slightly to almost completely red. I was said this is normal. You could try, but like Daiv says: 'better safe than sorry'.