300 to 500 bucks will get you a nice bike. like denis said get the bike, pedal it and you'll know soon enough. their so much to learn about road bikes in general; do stay with a name brand once you decide on a bike. when it comes to name brand components, you have shimano, campagnolo, sram, fsa(full speed ahead). each of these brands have their lower end upto their high end goods. cruise the internet for more info if you're curious good luck and welcome to the wonderful world of cycling.
oh and a cruiser welcome
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