Cokers are their own product. Diamonbacks take other brand tires, shave the redline groove in them, and attach the red paint. (in a nutshell description)

Cokers are hard as a rock. They are very brittle when mounting. They are almost impossible to balance, give a harsh ride, I could go on and on.

I thought my first set were just old, but then I picked up a new set from a member here, and they weren't much better.

I have (gasp) original firestone bias on my red 'vert, and they ride 100 times better than the brand new Cokers. The only reason I have stayed away from Diamondbacks myself is they 'look' a lot different than stock, original bias ply tires. Pretty sure thats the direction I will go from now on though.