Madbull barrels are fine...sometimes. I'm running one in a build up I did with fantastic results as well as in a p90 I used to have, while my groups tech has tried them twice with bad results. I think for some reason they are either hit and miss quality wise or just picky with the rest of your setup. For this reason I would stay away from them unless you already have one to try or know someone who'll let you test it out b4 you commit to buying off them.
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