I have one that I only use as a gerbil shelf. Hamsters have more sensitive feet and I think if they were walking on that kind of surface very often it could be an issue but if it's just one platform in the cage, and not one they're forced to use if they don't want to (i.e, it's not where their food or water is placed), it's unlikely to cause an issue but wooden platforms are much nicer and more comfortable in general so I would prefer them over a variera shelf. Also I worry about dwarf hamsters' legs getting stuck in the holes. It's probably irrational as the biggest holes are at most 5mm in diameter, but it still bothers me. So I just use it for gerbils which have huge feet.