Agreed.

But lets have a bit of a history lesson.  Back before the AWB expired and before Colt had it's own M4 clone all they built for the civilian market were HBARs carbines, and they used shortcuts like plastic buffers had for a long time had funky additions to prevent the use of M16 bolt carriers.

Back then if you wanted a rifle with a chrome line 4150 barrel (especially in a lighter weight profile) Bushmaster was the option - and they produced a variety of rifles that generally worked very well (most of my ARs are Bushmasters from this period).  But they never fully followed the TDP.  But during the AWB if you wanted a lightweight carbine - or an M4 look-alike with a chrome lined barrel it was Bushmaster or Armalite (and Armalite didn't use 4150 for those that cared).

Even after the end of the AWB Bushmaster sill used cheaper commercial spec receiver extensions for their telestocks, lack of extended feed ramps, and there were consistent issues with staking of the carrier keys, and a few other small nit picking type things.  Now granted these issues don't effect 99% of the owners/shooters here.  The rifles are good, but not quite up to the TDP.  Colts on the other hand were much closer to the TDP (as they wrote the Technical Data Package) and you won't find those issues on their 6920 carbines.

Comparing apples to apples (Bushmaster patrolman carbine to a Colt 6920) the Colt is a better rifle, but it will cost you more.  Is that extra cost really worth it to you?  Again for 99% of the shooters here the answer is probably not.  On the other hand if you want a specific kind of rifle (say a nice varmint rig) you're going to have better luck finding what you want (or ordering the custom upper you want) from Bushmaster.