I use a 4x lens on my HHA optimizer and I love it. I don't use it for shooting 3D tournaments or for hunting, but I use it all the time for shooting winter league. It really helps enlargen your target. For me...instead of floating around the white on a five spot, a lens allows me to float around the 'X'. I've thought about using it for 3D tourneys and hunting, but have always feared the glare issue. I would hate to be pulling back on a nice buck just to have him catch the glare from the lens.

But is will always use it when shooting indoor leagues and am a big fan of them.