Uh, I don't quite agree with the single speed for the OP.

1. Chicago may be flat (is there truly such a thing in Nature?), but it's also known as the 'Windy City'.
2. This bike is intended for both commuting (currently short distance) and longer rec rides in the future. OP might be planning on getting out of town to ride on terrain that SS gearing won't be the wisest choice for a noob to cycling.
3. While the SS isn't quite the same as a FG, the OP is a Clyde who is just starting out. He could wreak havoc on his knees without too much trouble while battling the headwinds.

I'm a Clyde and what Zrane said about the wheels is correct- and it's also one of the first things that manufacturers look at when building to hit a price point. Also, something else that I've come to understand is that heavier doesn't always equate with sturdier.