RE: Father and Son getting into the hobby.
That all depends on how quickly you pick up new skills, as well as what kind of flying you do. If you plan on doing mostly indoor flying, it is a great bird to have around even after you are proficient in heli flight. For outdoor flight, you can only fly it on calm days. Many new heli pilots get bored of the CX/CX2 within a month or so. The next step would be to a Blade 400 if you get a sim. practice, practice, practice, and put on some training gear. If you choose not to go that route (I highly recommend the previously mentioned route), you could step up to a fixed pitch heli next. They really can't do much more, but the will sharpen your skills as they do have a tail rotor/single main rotor and require more to control than a coaxial (CX/CX2). I would recommend staying away from a CP heli (electric motor driven tail) until you have gained more experience with a more stable heli such as the Blade 400. I'm not knocking the CP by any means, I have one and thoroughly enjoy it, it's just to squirelly for someone just starting out.
That being said, a simulator is an invaluable tool if used properly. It's best with a sim, to practice hovering until you can get that down, then move on to hovering in different orientations, forward flight, etc... Some "fun" time is a given (read: stuff that you are incapable of, i.e. 3D), but just remember to practice good flight habits on the sim as you would in real life, and practice the basics more than the "fun stuff".
My recomendation, is to get a CX/CX2 to get you flying, get a sim, and then to a belt/shaft driven tail bird with training gear.
Welcome to the addiction, err fun.