I'll give my two cents, then duck for cover while the certified trainers throw rocks at me.
Airsoft makes several mock ups of real guns, as are all aware of. I have one, and have attached some weights in it for one simple reason. Living in a subdivision, the neighbors would get kind of wonky if I went out in the back yard and started quick draw fire exercises, but with the airsoft (weighted pretty close to my .40), I can literally stand in my living room and shoot my ass off, because those little pellets aren't going to do anything but excite my cats.
The dog? He just looks at me like I'm retarded.
Point is, don't get locked in on the 'gotta go live, gotta go to the range' mindset.
Hell, you can go to Wally world and buy a little carnival type shooting game for the Airsoft and pop away at it all night long if you want, but the point is, you can still practice, and it's cheap as hell.