Not quite true. They were available in smooth, radial lined, and waffle patterns. Trucks and heavy duty applications typically had either the radial lined or waffle in the forward, direct and intermediate clutch packs. Higher end cars like Cadillac and the like used only smooth plates to the best of my knowledge. Again, just my experience.
A couple of good performance builders I know, will also use the HI ENGERGY friction plates as used in the 518 and 618 series of transmissions. A lot depends on how hard you're going to beat on the thing and to a point the builders experience. In your situation though, I'd go with the performance with the ALTO'S.
