We live in Colorado and my businesses are here.
As I understand the recent laws passed this past month, almost any semi auto that you own is not legal due to the magazine detail restriction in Colorado. However, almost all County Sheriffs have stated that they do not intend to enforce the laws. Nothing has been reported by city officials.
Also, based on the new laws, if you come to Colorado for hunting, or shooting of any kind, do not hand, or loan, your gun (any gun) to another person, even your wife, children, friends, etc. Even a "transfer of possession" for just a moment is a violation of the laws. Even teaching safety rules, or loading procedures, etc., to another person, by handing them a gun, or if they hand you one, is unlawful in Colorado now. Transferring any gun from the hand of one person to any other person, even momentarily, makes both a criminal in Colorado, based upon the new laws.
You are welcome in Colorado but be aware that there is now a mass of confusing laws. How much of a problem will be caused is still unknown.