Looks like the build-a-bikes have options for adding a second hub, and configuring it as fixed/free for an extra 25. I really don't understand the $200 price difference between the prebuild and build-a-bike when the only additional thing you can really customize is the color of the wheels, hubs, and cogs, as far as I can tell. Hopefully I wouldn't be asked to pay the build-a-bike price just because I want white rims when that's the only option I'm not already given with the prebuild. If I am, I'll just have to rock them black.

edit: that and the fixed/free configuration

At any rate, hopefully they'll be able to set me all straight when I call them.