I dont know about the Colt - but I love my S&W - the Sig is also a great gun - downside being the bolt doesnt remain open when mag is empty which is a pita in competition. The other downside is that they are not compatible with AR parts. Now the H&K looks and feels like a real gun - but I haven't shot one so I dont know if Umarex was able to get that part of the equation correct.