You said "think" so I am guessing that you are guessing that it will be a Christmas present. If so then "congratulations". The Ultrasport is a great little bow. Hoyt's new ribbing tech. makes the magnesium risers much narrower and lighter to some extent. The grips are about the same diameter as the machined aluminum models which means they are very low-torque.

I think your choice of draw length range to be a good one since you are giving yourself some room to grow. The draw weight range is also good since 50 lbs, for now, should be somewhat easy to draw for a person of your age. When you get older then you can always crank up the weight if need be.