Personally I don't see a great deal of difference in final painted model and material the model is made of.
If the material captures the details, then the model will look the same after you cover it in paint
Reaper has a "bones" material that they have started pumping out a lot of models in (they have a kickstarter running at the moment if you are interested in getting a bunch of models) - it has been a little hit and miss on a few models in the range but most of the figures you cannot tell from looking at a painted/undercoated model that it is made in "bones" rather than metal, resin or plastic.
However, some people swear by metal models, while others prefer plastic. Personally metal is a PITA as it is heavy and often requires pinning. Plastic is better for modelling and converting (
IMO).
Resin is often brittle so dropping resin figures or using them in regular play can cause breakages.
Bones is a PVC which is slightly bendy but holds paint and detail pretty well.