Wouldn't you rather have your dominant and most co-ordinated hand on the wheel at all times ?
I have driven LHD manual cars and have not found it a problem changing gear with my right hand, it is really not a problem.
In a longitudinally mounted engine the torque will tend to cause the car to twist in an anticlock direction, sitting on the right the car is better to counter this, hence so many vintage racers were RHD.
Finally most race circuits run in a clockwise direction, RHD allows the driver to be closer to the apex on corners and counter the roll of the car.
Apart from all those reason there are many reason for LHD being the best option, no least because the Geo Metro is not available in RHD

Ben