Mags are essentially the valve. Yes, the body changes the look, but many aftermarket manufacturers couldn't purchase the valve from AGD, add their own body, and sell at a reasonable price to make a decent profit. Especially, since they couldn't offer any performance upgrades. With cockers, a custom body and a few changes to the internals would change the performance, so it was easier to market from a private label point of view.
Originally Posted by OPBN
Smart Parts did offer a smart mag that had their barrel as well as valve upgrades such as the magic box and ported valve back.
PTP offered custom mags and emags. They were essentially body kits with custom logos on the valves.
SFL had a custom emag that was a predecessor to the X-mag. Again, it was essentially a body kit that used an AGD valve and electronics.
Except for the Automag in front, its usually the man behind the equipment that counts.