Replacing the hardware is the main mod. Early on, quite a few bit the dust from control linkage failures. I watched a brand new one go in because the pushrod pulled out of the elevator clevis. Someone reported a bellcrank that wore out in a short time. Tom Morris sells a complete conmtrol system package for somewhere around $30. Bellcrank, CF rods, the whole bit. There were a few reports of kits that had alignment problems. So check the incidence carefully. Otherwise they have been really fine flying models. The Tutor is very good, also. Ditto-check the hardware.
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