I have two Mark II's competition models and one Mark III 22/45 with bull barrel. The only complaint I have about the Mark III is the rear sights are non adjustable. I'm having mine removed and installing aadjustable sight like what is installed on my competition models. As far as accuracy is concerned any of them are extremely accurate and I've never had a problem with any of them. We shoot up to 1,500 rounds a weekend through mine with no troubles at all. I've found out if you use the cheap bulk ammo you'll occasionally have a misfire due to a bad shell but it is no problem to eject it and keep shooting. Mine seems to prefer the Winchester or Federal brands. The only one I've found it won't shoot very well is the CCI Stingers. The case seems to want to hang after it is fired.