I have a NIB 17 that I want to start competing with (complete and absolute newb), and I've read a lot of threads on which sights others use, but I'd like to learn why are factory sights so bad? What are the ideal characteristics for a competitive sight? When people mention sight sizes, I suspect sight radius is important, is there an equation that would help me isolate sizes to radius so I don't buy something too big or too small? I don't have friends who shoot non-stock guns, so I have no access to trying other sights to find out what I like. I'm going to have to take others opinions and maybe some mathematical analysis into account when deciding on sights.