My thoughts on lasers....
I think a laser can be a very useful tool. Unless you cannot use irons due to vision impairment a laser is NOT a replacement for iron sights and should never be used as such. But... as soon as my weapon clears leather I can, if I choose to push the button, see *exactly* where a shot will hit. My body position does not matter. Strong hand, weak hand, sand or blood in my dominant eye, thug #2 trying to get the weapon away, the dot is always within an inch or two of actual POI, regardless of range. If I can see the dot with either or both eyes I can hit that spot. I also know that if the dot isn't on the bad guy the round IS going to miss and may hit somebody else. Like anything, a laser can fail. That's why it should not be a replacement for iron sights or practice with them. My carry weapon has tritium night sights and a laser.
A red laser is relatively useless in bright daylight. A green laser is better in daylight but the beam can be seen by the naked eye at night, tracing a line directly to your weapon. A laser is another tool that could be the difference between life and death. For either you, a loved one, or an innocent bystander three blocks away. It does take practice to become proficient with a laser, like anything else. And it can fail, like anything else.
On the subject of Crimson Trace and others: I never liked the feel of lasergrips or the location of the button, which can easily be pressed accidentally with "death grip" under stress. I also found that on a friend's 1911 with CT grips my trigger finger would sometimes block the laser while exercising good trigger discipline. I bought a Lasermax guide rod laser for my XD45C. The on button is in the center of the takedown lever, which is the trigger finger index point that I had previously trained myself for. The "button" is actually a detented sliding shaft, like a shotgun safety. Centered is off, pushed either way is on. The Lasermax is also a pulsed laser, meaning it blinks very rapidly. This makes picking up the moving dot much quicker and also extends battery life. The only downside I've found with this particular laser is short battery life. It will only run about an hour due to it's extremely small size - the whole thing including batteries is contained completely within the guide rod! Batteries are about $4 a set in bulk off eBay. I switch out to "practice batteries" for range work and always keep a fresh set installed for carry.
I suggest that anyone who can afford a laser really ought to get whichever one suits them and Practice! Practice! Practice! If, after putting a couple thousand rounds downrange with the laser you still don't like it, you can sell it on Gunbroker or eBay for 80% of what you paid. I guarantee you're shooting will have improved more than enough to offset the 20% loss you take on the laser itself. You can SEE a flinch or pull in real time with a laser. You can also watch where the POA goes under recoil. You can trace the exact path the weapon takes while drawing, holstering, and changing positions. I've had my wife watch my right thigh for a "flash of red" when I practice a fast draw. Once in a while when I was tired the dot would sweep across the outer inch or two of my thigh.
I *never* would have known that without practicing with a laser.
Used properly a laser can be a tactical advantage and I'll take all the advantage I can get.
