Larry,
Assuming these are for AX only.
V710 - Excellent as long as you don't overheat them. Then they get greasy.
A6 - The choice of rich SCCA racers. Great tire, but does not last a long time.
R1's - Longer to come up to temp. Heat cycle out well before tread is gone. More similar to Hoosier R6. Not best choice for AX.
Toyo RA1's available in your size. Not quite as much stick as above tires, but very predictable and they last a very long time.
My $.02 only!
Chuck
