Got the big dot on my G20 and love it. LOVE IT. While I do acknowledge the logic behind it being a poor choice for longer distance shooting, perhaps beyond 15 yards or so, my results on the range contradict it. The single thing that shocked me was just how accurate I was out to around 20 yards. Very tight groupings for my skill level. This sight is incredible and I will be putting it on other guns for sure. As you can see below, the front site doesn't stick up much higher than a standard site.
-Dan