I don't think precession makes it turn better in either direction, does it? I thought precession just resulted in a nose up pitching force when turning in one direction and a nose-down pitching force when turning in the other, depending on the direction of rotation of the engine and propellor. It doesn't do anything directly to turn rates, AFAIK. Of course, if the aircraft becomes hard to control when turning in a given direction because of precession, that may well influence the turn rate because the pilot will be reluctant to push his luck.

Cheers,

RD.