I said "Masonite type" so the reader could relate to the type of product. The stuff I have has held up for years. Did the inner panels of my 48 Ford, 57 Thames, T bucket with the stuff in early seventies and has done great thru all these years of Michigan weather.
I've sold sheets of the stuff to others and never had a complaint. Seals up well with a coat of ordinary exterior house paint.
Presently doing the door and interior panels of my Gasser with the material.. Will post pics soon.