No problems with the barrels. From my personal experience, barrel interchange just isn't an issue. I haven't seen a barrel that won't mount on my contender or any of my buddies, and we own a whole range of frames. That's what they are supposed to do. Are there exceptions? Yup, but I haven't seen one, so enjoy and don't worry about it too much! And welcome to our obsession. Save your pennies, because 2 probably won't cut it once you get going.