I purchased one of the first units they made and it had a nylon roller. After two years the nylon roller cracked where is was attached to the axle. It cracked at a set screw which tightened on to a flat in the axle. The replacement resistance unit uses a nicely machined metal roller. I would not have any qualms on buying a new trainer from CycleOps, their customer service was top notch and they treated me well.