Spend a few extra bucks and get a Colt. Remember, with the Colt name, it will keep it's resale value if you ever need to sell or trade it.
And, of course, it's one of the very best as well.
I prefer the LE 6940, but the less expensive LE6920 will also serve you well.
Just my opinion for whatever it's worth, but I'd avoid the Ruger.
Resistance is futile. You will be assimilated