RE: Which type servos should I use in a bipe?
"How much can I save if I can use the Hitech receiver and will it work with 2.4 GHz? "
I may be wrong, but at the moment you can only use a Futaba receivers, R606FS, R607FS, R617FS with the new 2.4Ghz. systems. You can use Hitec FM receivers with Futaba FM transmitters.