I'm currently shooting an IBI 22" 1:16T Olympic profile. I shoot mostly 50m, 100m and 200m. Only a couple hundred rounds through it so far, and it appears to shoot about the same as my previous barrel at 50m/100m, but noticeably improved my groupings at 200m with the same ammo (Eley match). Haven't played with action torque yet, so there may be more performance to squeeze out of it.
Another guy who I shoot local bench matches with is waiting on an IBI 26" 1:14. He shoots PRS too and from what he's been told the 1:14 is supposed to help for distances beyond 200y/m. The theory is slightly lower velocities, but a faster spinning bullet should be more stable over a longer distance.
There just aren't many out there in that length and twist rate yet... gonna need some people to be guinea pigs.