No experience with Dynamic, but i am using the 4D Ultimate SB2 H, copper version and before that i had the Yatra 2 H copper version also. Seems that the copper version is the most popular for Zyx cartridges. Ultimate series is an upgrade to the previous range, has a quiter ride for a start, is more organic, has a fine frequency balance, voices sound clearer with even less sibilance, and shines when the music gets more complex. These observations come from having heard the U100, U Airy and compared to previous 100, Fuji and Airy. But as i understand these changes do not come alone from the CF cantilever, but from additional ones in the internal structure of the cartridge.
