I have them for sport/target shooting and personal defense. I've never had a question about it working or being on target on the Glock. (Maybe I will now that you mentioned it...lol.) I also think the decision to shoot/no shoot should be made before ever sighting with anything. (It might be different in a pissing situation though.) BTW, thanks for the serious, no bullcrap reply I seldom get on these boards.
Question; I do two types of shooting; deliberate, by the numbers target shooting, stance, grip, aim, front sight clear, rear and target kinda fuzzy, breathing, squeeze...just like the NRA done teached me and I also try and simulate an urgent situation; do some push ups, get my heart rate up, hands little shaky and try and tell myself 'life or death! shoot or no?" where it's all about getting the gun off the table, or unholstered or off the ground ,whatever, and pointed at the target, point shooting, and I don't decide UNTIL I am on target and make myself 'see' threat or not threat. You can work yourself up into a pretty good level of excitement much like hunting where you are avoiding tunnel vision and think in terms of 'do I have a good shot? What's behind the target?' etc.
The question being, to me, if you are using a laser for both THAT is when I would be worried about trusting them. SO, to me, I separate the two; the fun guns, the toys, and the serious business guns. The toys are not in reach in the house because I do not want to trust them when it matters.
So, consider that. Maybe someone will come along and tell you they are rock solid trust worthy. A Novak can get misaligned but, at pistol distances, point shooting, instinct I ain't using them anyway.
Lot to consider and with guns, it is ALWAYS a good thing to think it through, a lot, revisit it, keep it as an ongoing, evolving thing.