I'm not yet 18, but want to start researching some guns so that I can make the right choice when I am old enough. I'd just like some recommendations from experience with some M16's that are full metal. I don't want to have to upgrade it too much. Just please suggest a brand (I hear Classic Army is good, but I have no experience). This gun will obviously not be bought yet, but I'd just like to read some reviews on a few. Help is much appreciated!