I have Proof CF wrapped and SS barrels, and my most recent rebarrel is another CF wrapped proof. Like most things on the internet though, most (not all) people that claim they are bad have little to zero experience. I was told by.....I once stood near...I read on the internet....
To me, the primary purpose of a CF wrapped barrel is to stay relatively long, relatively lightweight, and retain adequate O.D. to properly thread for a suppressor. If you're not using a suppressor, I'd probably just go with a steel #5 (bartlein 3b). I'm not worried about CF wrapped barrels, and if you just want to spend money on looks or feel, that's reason enough I guess, but there's not a real purpose for you IMO.
For barrel manufacturer, I have benchmark, proof, & bartlein, and I've had a good experience with all of them. I'd probably default to what your smith wants to use and also has on-hand. If your smith doesn't stock barrels I'd either find a new smith or pick a barrel that would ship today.
As far as length is concerned, I have 24" and 22" in both steel and carbon fiber wrapped builds. It depends on the overall build components and barrel contour to get a rifle to adequately balance. Both can work fine. Personally, for a 6.5 PRC, I'd go 18" with a 140 (ish) class bullet.
I’m “breaking in”/ sighting in a brand new Proof cf wrapped barrel as I type this. Here’s the last (3) 5-shot groups from this morning:
Factory 143 ELDX
View attachment 528112
Adjusted 0.1mil right, then shot this
View attachment 528113
Trying out some Berger factory 140’s. Sitting from a tripod
View attachment 528114
So 5/8 MOA or better so far for 5-shot groups, which is also my general experience with SS barrels using factory ammo.