I'm glad you have had good experiences with RC-Expert. I advised them to post a disclaimer of "almost RTF" instead of RTF.
My tail belt drive pulley has come loose from the spindle which connects to the main rotor gear. If you notice unplanned tail spins this is most likely the problem. Rather than tear apart the case and replace it I put some CA on top of the gear where it contacts the spindle. I cant blame rc-expert but most builders put a drop of CA here to cement the spindle to the belt drive pulley.