Many of the stock mixing boards run into difficulty running 3S LiPo packs. If you know that you are going to advance to the point of carrying an onboard camera, you should seriously consider going seperates. A decent HH gyro (Futaba gy240) and 2 ESCs are all you need. This behaves much better than the mixing boards, and lets you run 3S LiPo, for the extra power and duration. If you are using a stock tail motor, you will want the tail ESC to ba a high frequency one (TREC or Schulze slim 105). You also might consider going brushless for the tail, or main and tail.

The 4500mAh LiPo will be too heavy.