Lasermax and the one that starts with a V but they are expensive. Almost as much as buying a New gun, the one with the that is. The Lasermax runs $140 retail.
Viridian green lasers is what you mean. And I've heard good things about them,yes they are 200+ dollars retail though. But I saw one on a friends gun and he can see it clear as day 100 yards away on a sunny day. Says it'll take a beating to
Between the grips and guide rod laser, I'd say the guide rod laser because its pointing straight forward and not off to the side like the crimson trace which are only accurate to about 50 yards but its more than you really need. The guide rod look is more stealthy
I have the Crimson Trace laser grips on 3 of my handguns. A Glock 19, a S&W 640 snubbie, and a Taurus tracker .357. I have them sighted in for 25 yards and I can shoot groups a lot tighter using them than I can using iron sights. I haven't had any problems with them losing adjustment and I like how they turn on instantaneously when the grip is squeezed. I also have a S&W bodyguard .380 with the built-in laser under the barrel. It gets covered with powder from the muzzle when shooting. Not sure if the internal rod lasers do that also.
I like the Crimson Trace because when you grip your gun you don't have to fumble around looking for the on off switch.
“There are hundreds of millions of gun owners in this country, and not one of them will have an accident today. The only misuse of guns comes in environments where there are drugs, alcohol, bad parents, and undisciplined children. Period.” Ted Nugent