1) STANDARD.
2) I'm partial to aluminum, but to each their own.
3) Dura-ace is lightest. The cassettes are actually less durable than ultegra. Sora have bad (in many people's opinions) shifters, with less gears. 105 is a great compromise; I have ultegra; depending on your budget, you won't go wrong with either, assuming you're buying Shimano.
4) I wouldn't buy a bikesdirect bike as a newbie.
5) Building your own bike is more expensive.
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ElJamoquio didn't hate the world, per se; he was just constantly disappointed by humanity.