Anyone have any experience with these Holographic sights. They look like a square frame of some sort mounted on top of your pistol? I have been told that target acquisition with them is real nice & real fast. Don't know what kind of magnification they have, if any. Anyone have any experience with them or know anything about them. Thinking about a sight swap for my 345 ( that's in another post) but thinking hard on holographic for one of my 357's.