Does not work well on g19 gen4 - Killer Innovations Velocity Glock Magwell

I see from other reviews that it either fits or it does not. Mine definitively did not. The magwell itself is fine and appreciate the fact that it can be used with or w/out the backstrap(s) of your choice. It is also stiff enough to not slide off the front grip "bulge" when installed - no issues there, but that alu plug is excessively tight and expands the grip so the mag had to be pulled very hard to get back out (same going in).
2 hours+ with file and a Dremel tool finally made the plug fit and the mag drop as it should, but the rounded backside still interferes too much with the little tabs on the grip insert (if you are using one) and ideally needs additional grinding in those areas.
The final result is a considerably modified alu insert - which I do not like on a carry gun, so I will find another magwell from another manufacturer for the (carry) gun and install the KI unit on a plinker (or leave it in the drawer)
And before anybody asks, yes, I double checked the delivered part for correctness in way of model # vs the G19/4