I've built 3 (2 Hungarian AMD 65s and 1 Romanian "G" kit, working on a 4th and final. A buddy and I bought some of the rivet jigs and 100% receivers. I'm working on an 80% receiver now. It's fun stuff and once you take one from parts to complete to the firing range, it's very satisfying. Definitely a learning process but tons of info on the web.