I have not ran the Bartlein CF barrels, I’ve ran their steel though.
I have and do run, Proof CF and Proof Steel.
I am a recreational shooter at best, so keep that in mind. Others may be more qualified.
They are all fantastic barrels. The analysis you’re trying to do will end up causing paralysis by analysis.
Get a barrel you like and roll with it. Unless you’re putting thousands of rounds down range a year, or shooting in some unique use case, you won’t tell a difference. Maybe a few percentage points here or there but it’s going to be hard to tell behind the gun.
You can slice and dice this 100 different ways but at the end of the day, it doesn’t matter what gear you run. If your skills are not up to par a gain twist barrel or 400 MB barrel is not going to seal the deal for you.
And, no matter what you pick, it will be lacking somewhere. There will always be a void. Sometimes it will do x better but lack in y. Vice versa.
Edit:
To the short barrel point, I would get whatever one you want or is in stock and go. I personally don’t think the brand of a barrel from Bartlein or Proof is going to make a difference. They will both be excellent.