if the BX25 mag still is not reliable with the roller job on the follower (mine wasn't),, try adding some duct tape to the mag body... two layers to the rear, and one around the side were needed to tighten my BX25 and BX15s... the lock up of the magazine front to rear is loose on the high cap mags compared to the OEM 10 round rotary mags....there are a couple of videos on youtube where epoxy was added to the BX mags.... I wasn't successful with 2 part, but have not tried something like Marinetex
I believe the looseness of the mag causes problem ejecting the case, as the ejector is on the feed lip... I have one mag where simply squaring off the ejector caused an improvement in reliability