Do yours have the original cones or have then reconed? Some aftermarket recones can have slightly different materials...or the factory could have changed cones. Look and see what the Pro 15s looked like in the GN on the USD page...I thought they had ribbed cones but I could be wrong.
Emilar is still in business as Plus-One Engineering. Can find specs there. Well, they were last year when I looked...lol.