I had my first lower apart and realized it would be good chance to show what the PRI Gasbuster Charging Handle has done to this lower.
First you can see how the gasbuster has carved two channels into the lower. The ears of the gasbuster make it larger and easier to use also have rubbed the finish off the lower. On the left side there is a damage where the roll pin that holds the latch in place has walked out and gouged the lower. Newer Gasbusters use a solid pin in place of the old roll pin that was known for breaking.
Lowers will normally worn from the charging handle rubbing against them but I have never seen this much wear from any other brand of charging handle. Now this might not be normal for the PRI charging handle, this is a RRA lower and there is the possibility it might be out of spec and taller than normal. But I am lead to believe that it is the PRI product at fault in this case.