Tippmann 98 Custom Pro
Proto 1 PC Barrel(black)
Anything, I use $30 per 2,000 paintballs and they seem to work fine.
Accurate, and moderately quiet barrel. Works well especially at close range.
Not many, but it isn't the greatest for long range(100+ft).
I purchased this barrel and have played with it twice, both of the times being very impressed for the performance coming out of such a cheap barrel. I purchased this barrel for $30 and can't complain. I will admit I was expecting better performance at long range, but that could have something to do with the slight wind I have experienced the last few times I have played. Don't expect to be sniping people from 150 feet because it wont happen.
All in all, if you are just a casual player looking for a good cheap barrel then this is the one for you.