I have the CT lasergrip on my S&W model 60. While I prefer the factory grip the CT is just fine after I became accustomed to shooting with it.
As an Instructor once told me, you don't use your laser as a substitute for your iron sights. You use the laser when you are unable to obtain a traditional sight picture (as when on the ground, shooting from a low position or retaining the gun while grappling with an attacker). That is where the CT grips really shine (pun intended). I keep mine adjusted so they are parallel with the bore axis rather than trying to co-witness with the irons sights. That way it doesn't interfere with my normal sight picture but if I need to use them, I know that the muzzle is pointed just ~1.5" UP and LEFT of the projected dot. This is fine for short range, defensive shooting scenarios.
Do I think it is a "must have" feature? No, but I think it is a nice feature to have.