I should preface this entire post by giving you a disclaimer in the fact that I'm pretty boring when it comes to lenses. I don't like crazy and outrageous colors and patterns, and tend to favor lenses that will compliment my medium brown eyes. As I mentioned before, circle lenses are mostly worn in Asian countries. In my trials with these lenses, I've learned that many lenses look best on a dark eye. I've purchased lenses, thinking they would look so amazing, but it turned out that my brown eyes were too light to see some of the patterns! They just look bigger and muddy, but not as cool as I was hoping they'd be :(
For example, many lenses give me the appearance of having a peep hole in my eyes. Which I don't like. When your eyes are dilated in low light you don't notice it as much, but if you're inside with bright lights you can normally see parts of your iris (in my case the brown part) in the small pupil hole. The darker your eyes are, the less noticeable this is, but it's always been something that bothers me when I'm wearing lenses.
Here's my "peep hole" with a pair of Fresh Look color contacts. Regular color contacts usually look fine because they tend to have a translucent color towards the edge, so it's not so obvious. With that out of the way, it helps to better describe why I prefer one lens over another, though they might have the same color and similar patterns. I try to avoid that scary vacant stare at all costs.
Now on to the lenses!