LOL. I agree with Slynk And Michelle. Those little dings shouldn't cause as much problems as you are seeing in #3, but may be very interesting when shooting into the light. And WEAR SAFETY GLASSES. You'll really regret it if you don't! Do you have problems in general with Sigma lenses? I love my Sigma 180mm macro for the canon eos. I hate my Sigma 170-500mm zoom. The 180mm macro is my general purpose lens, and is the best I've ever had (that I could afford). The long zoom is crap.