I have about talked myself out of buying and using these but would be interested in discussion and experiences from you guys.

The obvious pro's would be of saving ammo and the device would pay for itself especially on guns that use expensive or scarce ammo. Another pro I see would be not having to go the range and something you could use in your yard if you live in a residential area where discharging a firearm is illegal.

Cons that I can imagine is: how accurate is the alignment? In reading about the best bore sighter reviews the universal types are favored but those pictured are kind of bulky and the bolt can't be closed. To me this would seem to be a pain on certain semi autos. Other cons speak of extremely short battery life and some that don't have on and off switches. The most common seem to be those made for a specific caliber and I would have to believe these would fit more snug but again there's the cons and these don't seem to be stamped with a manufacturer's mark so you can't compare one brand to another.

Experience's or opinions?