Part No. TG93HA Does anyone have experience with one of these? I love having night sights on my hand guns, and this seems like a dream come true for a single shot standard barrel 12 gauge. Says it fits most 12/20 gauge barrels. A lot of good reviews online, but you never know if reviews are legit. They are about $20 on eBay. Cabella's has them also. Worth it or waste of money?