what are you puting it on?
a pistol?
i can see that i suppose,although i would prefer some good sights.its usually not a great idea to be searching for a dot on your target,when you have sights right there for the using imo.
a rifle?
get a good red-dot sight(Aimpoint),it will work in much the same way.only you never need to search for the dot,its always right there.
what purpose?
i think they're good for training,but not really practical to depend on for SD/HD or even hunting.not only the "searching" i mentioned,but they can be a target identifier.
just my 2 cents.