all of them...its buggy there's an issue.
I beg to differ,..... A LOT of heli and plane guys trust Hitec to their 500.00-10,000.00$ rigs....Hitec is one of the Best Flight radio's you can buy and IMO if the plane/heli guys can trust it 1000' away....Ill trust 150' away.
they keep your Ring and pinion as true as possible as the plastic wear out over time they will cause the R+P to loose its mesh and reek havoc....You want the Inserts, Trust me.