Which lower would you get?
Is the quality of the Colt higher than the Rock River?
I have a chance to get either.  I don't mind the slightly higher price if the Colt is better.

Your advise and opinions please.

Well, I'll tell you what. I just got myself a fresh-off-the-press RRA Tactical Entry carbinr. It is, without a doubt, the finest AR I've ever owned. The fit and finish is awesome. I don't think you'll be dissapointed with one.

Go with the Rock River Arms.  They are equal in quality, less expensive and use standard/mil-spec fire control pins.

I went with the Rock River tactical entry model as well. I got it over a Colt civilian M4 and am rather happy I did. Great fit and finish, very high quality rifle, and I just love those triggers.

I agree with the other guys, if you're looking for a good shooting, usable piece.  On the other hand, there is a certain magic in the Colt name, and that may make it worth the extra bucks to you.[:D]

They rather nice, aren't they?

I have a Colt, and I'm very happy with it. Resale will be better with teh Colt, but if that's not a difference than I wouldn't worry about it. RRA is a very good gun.

Colt has the side sling mount on the front sight, but that's probably the only difference.

Just, with the RRA, make sure you get a complete gun from RRA. Around here there are plenty of put togethors on a RRA lower, since (AFAIK) they don't mark their lowers differently.

Oh and "If it's not a Colt, it's just a Copy"
and, "Quality makes it a Colt"
:)

Edit: Whoops, you said "lower" not "rifle".
Colt individual lowers are take offs, so I would get the RRA or a DPMS in a heartbeat.

[b]RRA[/b], nuff said.

(Edited to add: Buy it with the NM trigger also!)