If you ever are on maui. Maui ammo and gun supply has a TiTraining simulator. Uses real glock pistols with a replacement barrel that shoots ir laser on to a screen. Its interactive and only uses 12 gram c02 cartridges. Lots of different scenarios. Home intruder, school shooting, etc. With multiple ways each situation can pan out. They have skill builder scenarios. And fun shooting stuff like cowboy stuff. Modern stuff. Shooting in the back yard, etc. http://www.titraining.com/

I have this..
http://www.amazon.com/exec/obidos/ASIN/B0089GEP76/?tag=2ahawaii-20

I like these because you can get adapter rings for different calibers and you can replace the impact switch when it wears out.  Other brands, you must buy extra units per caliber, and switch is non replaceable.

IMO, it helped me improve my pistol shooting a lot.  Great to instill muscle memory of the trigger break and control.  Then when I go to the range for live fire, I can concentrate on not flinching with the noise and recoil of the live ammo. Since dry fire practicing with the laser cartridge I have consistently been able to keep shots on paper, and have moved away from blasting my target frame legs.. Lol 

I've been thinking about getting this...
http://www.amazon.com/exec/obidos/ASIN/B00K7IT6BE/?tag=2ahawaii-20




pretty cool simulator that works with PC and webcam.   

not convinced I really need it yet. hehe

What I really like about these laser trainer cartridges is that you use it in the firearm you have; which teaches you the trigger pull of that particular gun.  Also, where these differ, and really shine from traditional dry fire, is you can visually see, when you break the shot, any slight movement of the gun.  Any trail of the laser, when the shot breaks, is an indication that one needs to work on trigger control. You can really tell the difference when pulling through a double action shot.