I was wondering what peoples experience is with AR "kits" that you can get from companies such as Del-Ton, J&T, or Rock River Arms. The kits are suppose to come with everything except the stripped lower. Is this true? Does the kit get shipped right to your home or to an FFL? Is Just the lower the only thing that needs to go through an FFL? What about the parts being Mass compliant? I see you can even buy AR pistol kits. What about the short barrels in those kits; are they legal as long as the pistol does not become a rifle? I know this is a lot of questions but I am leaning heavily toward doing a kit gun and am looking for what the down side is.