I have a S&W M&P 340 with a set of CTC grip already on it from factory, it's the kind that's in the first pic you posted.
As with any laser on any gun, I wouldn't only rely on it to aim, but it's a nice tool to have if you get stuck in tight & stressful situations and have to make a quick shot without aiming. At least then you'd have a reference dot. They feel a little different from the "normal" j-frame grip with the finger grooves, but they're not uncomfortable, just different.
Would I use laser at the range? I don't think so, other than to see what it's like... would it help you shoot better? No. but if you have to shoot in the retention position in a self-defense situation, it sure helps to see that dot on the BG and not the old lady behind him and across the street.
My 2 cents
