A towel radiator made from stainless steel is made to last. Stainless steel is less likely to suffer from corrosion due to the other elements in the alloy.  Guarantees that accompany stainless steel bathroom radiators are far longer than standard towel rails because of their longevity.  A stainless steel towel warmer is also more efficient as it's not coated in chrome or paint, which reduce heat output on standard towel rails.