I'd say this is the best advice so far.
Printable View
I would say look closely at the chart and decide if any of LMT's "shortfalls" (if you can call them that) matter to you. I will also say that Colt is listed first for a reason.
With that being said, I do own both. And can say that both are excellent carbines and either would/should serve you well. Now, if pressed, if I only could have one it would definitely be the Colt. As far as new/current carbines go, I am a little disappointed that LMT has gone to a MIM gas key. I've had my LMT for over 3 years, before they changed to the MIM key. As far as factory supplied carbines, the Colt comes with a M16 carrier and H buffer, and the LMT comes with a AR15 carrier and a carbine buffer. I can tell the difference too, but I do not mean to imply the LMT would cause problems. Just something else to consider (the chart will show this as well). If price is of any concern, I would say you could probably get a Colt 6920 cheaper than a LMT at this time. I got my 6920 somewhere around a month ago for $1099 and if you shop some I'm sure you can still get that price. Check out Gunbroker, I don't think LMT's are that low right now.
IMHO, I think both are quality carbines but I do favor the Colt. But it is your choice and there isn't a bad choice between the two.
I have an LMT.
the buffer swap was easy, and Im probably gonna change out to taper pins soon just for peace of mind.
the parkerizing under the FSB doesnt bother me (or lack thereof)
buy whatever you can get a better deal on.
Both are great, I just like Colt more.