I have now built 3 longbow strings of the X....a couple 18 strand padded to 24, and one 20 padded to 26. All are served with .025 62xs (dropping next string to .021) and are being shot daily on my Berry's. No silencers necessary on the Morningstar, but I decided to put some of Chuck Deshler's wool scallops on the Argos as its' a bit more high performance. I received a new to me Mohawk Sparrowhawk today and am shooting the same string without silencers necessary so far on it.
The biggest thing for me with this material besides its' inherent quiet and no-fuzz nature, is the utter lack of creep. On all 3 strings (after burnishing and initially setting brace height), I have had to add twists one time only within the first 25 shots, and that's it. Temps here have been in the mid to upper 90's for the past two weeks and my work schedule is such that I shoot in the heat of the afternoon till dark, so that gives you an idea of the stability.
I have only ordered white and tan, but I do notice that as the material diameters get smaller, the dyes and/or coating used plays a bigger role in the bundle diameters because of the large number of strands used in each bundle. This can cause you a few fits as you figure out your particular formula, but the effort in doing so will net you a really great string that should last a heck of a long time.