Jan Boyce Avocado cold hardyness ?

[Avoman]

Ive recently had some jan boyce scions take and ive never tryed one but some claim the jan boyce avocado is among the best tasting, but my question is for thoses that have tryed growing them in areas that can go under 30 degrees how well did they do without much or even no frost protection? I read on internet they did ok at 22 degrees but i dont know if that was for a large tree or a smaller one.