Recently purchased a x56 and I really like it, surely it has no significant changes from the x55 except the new joystick but it is solid.
Just like the old x55 it experiences issues with the throttle leading to having to quickly move it forward and back in order to calibrate( 0-100% instead of the bugged out 0-80%).
After purchasing it felt like I should of just gotten the warthog but then again its more money and also requires rudder pedals.
All up to you, if moneys not the issue I would just say go with the warthog and pedals.