My other primary the cyma o28u. Got this at the same time as my g&p m4 and tbh this one blows that one out the water. Maybe its becaus my expectations of the m4 where higher, as this would be considered as a low end gun and the m4 more mid to high range. Changed the foldable grip for an angled magpulstyled one, and a birdcage flashhider. I use king arms midcaps on it but the supplied highcap works as a charm too.