I have used the Vortex 4-16x42mm Diamondback HP rifle scope and I must say that it is a great scope for its price. The fully multi-coated lens provides clear and bright images, and the side focus adjustments make it easy to use. I had no problem counting horns at 400 yards and the HP seems to have an edge on other scopes that cost 200 bucks more for the same options. Overall, I would highly recommend this scope to anyone looking for a good quality scope under $500.