This barrel is an awesome barrel! I use it with my Mag. I have used all sorts of paint in it--Proball, RP's, Zap, Brass Eagle (yes Brass Eagle!) I have never had a problem with a lot of ball breakage or anything like that. Although I have had some balls break in the barrel (like 2) the barrel cleans itself out after a couple of shots. This barrel is very accurate, and is very cost effective.
This isnt really against the barrel at all, but I wish they made this barrel in a 14" version. Ohhhh, well LAPCO barrels RULE!
This barrel is awesome, the only other barrel you might want to get instead of this one is the Freak System--and thats only because of the diff. combinations you can make. But the Autospirit is well worth the money!