I think if there's one thing that's started more arguments, it's pistol sights. There's so much individual input on sights, and everyone has different opinions.
For example, on competition guns I like to run blacked out sights. Black front, black rear for IDPA/USPSA. I'll also run fiber front with a black rear for Steel Challenge or occasionally in USPSA.
Lately, I've been shooting a lot with 3-dot sight, and you know? I kind of like them. My big issue usually isn't with dots, but with how much light comes in around the front post.