I have the XS big dot on my glock 17, I love them. Their are a lot of videos on you tube you can watch about them. Very easy to be accurate with IMHO.
Laws that forbid the carrying of arms... disarm only those who are neither inclined nor determined to commit crimes... Such laws make things worse for the assaulted and better for the assailants; they serve rather to encourage than to prevent homicides, for an unarmed man may be attacked with greater confidence than an armed man. -Thomas Jefferson's "Commonplace Book"