I'm so glad I got a 2d UCD, the first one was a bear to harrier,snaps to inverted unpredictably, this one is almost unbelievable,harriers rock steady @ very HA ,looks wierd(but cool)so slow with the nose at a 45Deg. or more. It has to be all in the setups,CG's & wing loading too,1/2 lb less than the other one.Its not pattern smooth but with mixing & trims this plane is one to have for nothing but fun, I will have one as long as they make'em.