Never used one, but have seen and looked through one on an IPSC gun (if I remember correctly). Seemed to look good and would imagine it would work fine for someone with less than optimum vision. They are pricey ($200-250 rangeish) but are probably worth the money. If you have any hesitation, you might want to visit a gun shop and ask to see one or something similar. Some gun shops will order it in and let you review it before you buy. Others will not. It is not something I would want on my gun because I train for CCW. Best of luck to you on your research of this product.