I think you should get the walkera dragonfly #37 SE version. It comes almost completely upgraded with a lipo battery, a brushless motor, and more. It also doesn't have a tail motor so the tail rotor blade is powered by the belt driven system. I'm planning to buy it at www.raidentech.com for $250.
You can check it out at this link:
http://www.raidentech.com/206wadrfly37.html