This is the beauty of the FX STX barrel design. They can change groove/ land ratios, twist rates, chokes, with a few mouse clicks in the design software and produce one off prototypes to experiment with in a couple minutes of machine time with no changes of tooling.
.
6 months from now FX will decide the new liner will be even better with a factory installed Carbon fiber bonded sleeve. It would be very easy and cheap for them to do in production. No more droop or resonance even in the 700mm Crown/ Dreamlight bottle superlight barrels with giant moderators hanging off of the end