I'm interested in a new rifle, and am researching both of these options. The SIG is pretty tempting, with the $300 rebate offer, but it seems that even after that, the cost ends up about the same as a new Colt AR. I already have two ARs, so I could go for variety, or I could add to what I have, having the advantage of compatibility. What do you guys think? I am overlooking some pros and cons of each option?