I am a big fan of Crimson Trace. Their product is well engineered, ergonomically designed and manufactured to high standards. Their customer service is on par with S&W, the best in the firearm business.
Technically, it's nice to have windage and elevation adjustments, even though I've not needed to adjust them yet. I'm not a fan of replacing the guide rod as an approach. Early on it was reported that LaserMax had problems with battery caps coming loose and disabling the weapon. If my LaserGrip fails, the weapon still works aiming with the iron sights.
LaserMax must think the grip approach must have merits since I believe they are working on a configuration similar to LaserGrisps that do not violate the Crimson Trace patent.