I've never experienced a plane that rolls better one direction over another when the plane is properly set-up. For some, rolling to one direction over another "looks better to their eye" or "feels more comfortable on the sticks." I experienced this myself until I forced myself to practice both rolls (primarily point rolls) and knife edges in both directions. In the case of rolls, both rolling left and rolling right with the plane traveling both from the left to right and the right to left. I started working on the RealFlight simulator and then continued practice at the field.