Single speeds are great and a lot of fun, but for a utilitarian commute of that length, I think I'd stay with a geared bike. I still think you should get the single speed though. I converted by freewheeled single speed to a fixed gear bike and I really love it.
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I stop for people / whose right of way I honor / but not for no one.

Originally Posted by
bragi
"However, it's never a good idea to overgeneralize."