I was curious what percentage of LEO's here carry a duty sidearm with either a light or laser source mounted on their weapon?
  It seems to me that you guys have to be the experts to consult on the actual usefulness of these two accessories.

Alot of agencies do not allow weapon mounted lights for patrol officers. The reason is that people tend to point the light where they are trying to see, and with this setup you have to point the gun at the same thing. This is usually not the case with SWAT though.

Lights on rails under the pistol, laser, are, junk , unless you just shoot for fun. laser are hard or impossible to see in bright daylight, and the lights attached to the gun are just gizmos, use a flash light if you need light. In serious gun play with more than one laser equipped weapon, whose dot belongs to whose weapon,( if you've ever seen 6 or more dots jumping around on a target you would know what I mean) plus the laser provides a sorta traceback to the person holding the weapon. Plus the good ones are real expensive, and in my opinion not worth the money, I have tried some of the best Crimson trace , and have only one , it's on a Ruger Mark 2 pistol, a lot of fun, but not good for real" dirty work."

I use the M-3 on my glock when I clear buildings and such and also when I am with my dog since one hand is on the leash the other with the gun/light, if not I would have a flash light since I only have two hands, lasers are not worth the trouble.

Now first let me state I'm not trying to be antaganistic , but why don't you issue verbal commands to come out, then turn all the lights in the place on ,then turn your dog lose to do his thing.

Since we changed our policy two years ago, we've had a BUNCH of guys switch to Glocks, many of them with the M3 (myself included). Two hands on the gun is better than one. And it's hard to hold a gun, a light, and radio for backup at the same time with only two hands in a high-stress environment. Mounting the light to the weapon gives natural pointability to the light. Less variables.

And if you're one of those guys holding the laser equipped gun, you know which dot is yours.

Get the Safariland 6280 SLS holster for the Glock/M3, and install their HOOD GUARD and SENTRY options.

    Thanks!!! You guys answered my question better than expected. I have been considering the M3 for my Glock 19 and HK USP9F. The weapon would be used at home for bump in the night kind of situations. In my case I think the M3 addition would make it one less thing I have to hunt for in a stressful situation. While still giving me the ability to identify the noise and not redecorate the living room with the family cat.

  Be safe!