No gimmicks, no “learning” the trigger, and completely drop in ready.  Fostech has fine tuned a binary trigger to work like you want it to.  There’s no machining or tooling needed to install.  You really get what you pay for in the Fostech Echo ll.  There’s no more proprietary bolt carrier group, and no more out running the hammer/bolt issues.  You can shoot as fast as you want or as slow as you want.  We got the chance to try one in CMMG’s .45acp Guard pistol.  We literally drop the trigger in, and began shooting and have yet to have any issues.  If you’re looking for a reliable trigger to speed up your rate of fire, and have a duty style trigger without paying $20K for a pre-ban machine gun, here it is!  https://americanresistancegear.com/product/fostech-echo-ll-binary-trigger/

It’s got the safety aspect of it too.  If you don’t want to fire the second shot, simply hold the trigger back, move the safety selector to either semi or safe and release the trigger and it won’t fire the second shot of the binary mode.

With a price of less than $500, there’s really no argument.  You get what you pay for on this one.