I've mixed three or four medium and soft plastics from different makers together just to clear clutter. The only plastics I can think of that are not compatible are the ones that are supposed to be either super stretchy or a floater, and then I am not totally certain which has some vapor given off during cooking that is very very toxic. At one time I had plastics from Bear's, MF, Caney Creek and Do-It that were either soft of medium and they all got blended together and made wonderful baits.