I disagree BLS33. While waiting for my FFL I stumbled into the airsoft world thinking what the hell. I like many other firearms owners scoffed at the idea and absurdity of airsoft. But when I got my hands on a real one (not the cheap pieces of crap they sell in the minimarts, but a $200+ one) I was extremely impressed and let me tell you why
M4 (M16/AR15 etc..) Pick a model. Same weight, same size, same sights, same functions (for the most part). You do not charge it nor is the bolt release functional but other than that it is very similar. You have safe, single and full auto. As far as training goes it teaches you fire control and weapon location. Basically you are firing a live weapon minus the loud noise and recoil. You still have to switch mags when empty (if you use the thirty rounders) and still have to point the weapon in a safe direction. Standard velocity is around 330fps with .2g BB's and they have no problem shredding cans.
I use it to teach my daughter gun safety as well as firing techniques in my garage any time I want.
Did I mention the ammo is about $15 for 5000 rds?
Range is not that great (150ft) but it is not an issue for close quarters. I am more than happy to invite anyone interested to come on out and play a game. Find a local team and go watch them train or join in. Its the ultimate cowboys and indians.
Hope that brings a little light on the subject.