Lasers are great for Snap-Cap/Dry-Fire practice, as they let you see how much movement (dipping the muzzle, pulling right/left, etc) one has during trigger press, but I wouldn't rely on a laser for SD.
For low light/no light situations, I want to be able to actually see if what I'm encountering is an intruder, or a midnight muncher (without actually aiming at them), so no rail mounted lights for me. A rail mounted light seems to violate 'Don't point your firearm at anything you're not willing to destroy' rule.
So... if one of those toys is a Hand Held tac-light (and >200 Lumen), that's what I'd go for.