To keep things on track here I have machines with flybars both over and under the main blades. I really don't think there is a big difference. I've seen the subject debated ad nauseum on the net with no definitive advantage of one over the other. One claim is that with the flybar over the mains the paddles are in clean air out of the rotor wash hence better response and stability. The flybar under the mains gives maybe a little better linkage geometry.

I have 2 raptors and have flown a bunch of shuttles. I've also seen the sceadu and there are advantages and disadvantages to all of them. I honestly would consider it a draw between the 2 and don't think you could go wrong with either.

On Raptors the things that I'd change are the swashplate and washout hub. The stock, as well as the metal, swash plate develops a lot of play. They work ok but to really tighten up the machine put on a Quick UK Swash and a good tight metal washout base and it makes all the difference.

A friend that flies shuttles put a metal swash and hub on one of his and it flies much nicer also.

Again it's pretty much a toss up so chose what you are comfortable with.