Looks as though rite-cell is just a plastic foundation made by Mann Lake and plasticell is a plastic foundation that has a coating of bees wax applied to it. It's sold by Dadant.
Personally, I'm going with foundationless to avoid putting contaminants into the hive. If I was forced to pick one, I would go with rite-cell just because I don't know what might be in the wax that was used to coat the plasticell foundation.