If there is a design problem with the Nexstar, it would be public knowledge. Or at least it would show up in every Nexstar, since it would be designed into it. Since there are lots of Nexstars flying and flying well, it's a good bet there isn't a design flaw. What's left? Manufacturing errors or owner setup errors. And operator errors.

Not finding an error doesn't prove it didn't exist.

An airplane that turns hard left or hard right on takeoff before it reached "airspeed enough to take off" doesn't have something wrong with it's design. It's aerodynamic design hasn't even gotten the chance to work yet. It either has something wrong with it's gear or radio equipment or operating environment or operator.

Sorry but this thread has degenerated to trashing a proven design.