I have a Fullfield E1 on a Marlin Model 60 Stainless. It is a phenominally good scope. The optics are bright, crisp and clear. Absolutely no distortion even at the extreme edges. The floating ballistic plex reticle is very usable, even with CCI Mini-Mags . Love the finger adjustable knobs. At low powers, there is no noticable parallax even up close. You get a little at high power at close ranges. But even at max power, I notice none at even 25 yards. As far as robustness, I'd put a Burris up against just about anything out there. The Burris E1 is made by Burris in the Philippines. Unlike most companies that source products from OEM suppliers, Burris set up their own factory in the Philippines, complete with their own management and machinery to build certain lines of their scopes.