I may not be able to tell the difference, but for my newly acquired Valley I now have (a) an old (used) green logo CB (which I got for free); (b) a new purple logo CB; (c) an old red triangle Aramith CB (came with my very first set of Super Pros); and (d) a not-quite-as-old red logo Aramith CB (came with my second set of Super Pros that are now being used on the table).
I think I may have a CB addiction.
I intend to use the red logo mostly, but will play around with the two magnetic ones to see if I can notice a difference.