Follow-Up:
I replaced my contrans tires with Nokian NRC 2 Tires The front is thew same size and load rating as the contrans but the rear is a size larger (225/15) with a greater load rating. The difference in the ride is remarkable. The Rialta handles better and rides quieter and smoother. I don't have enough mileage to determine if they will last as long or longer, but previous experience that I have had with Nokian tires have been very positive. John 99QD Vermont