[Eagles6]

See post #17.

[MileHi]

Just more expensive and more hoops to jump through.

Yeah, I know. That's my point. If the ARs that are in common use had the option to have a select fire trigger group when they were purchased, most of them would have and they would be "in common use". And they are more expensive because there are no new ones. The select fire option on an AR or M1A might add $25 to a new one.