I have been using the Master Air Screw 22 X 10(I like the thicker airfoil they have) and was getting 6500 rpm. The engine/plane were very happy with this combo. Remember that I am pulling around 29# of war bird with the G-62. Not looking for the highest rpm but the best thrust. I prop my engines to run in the max. torque range(this will probably set off some more comments) on big war birds. Big Bird said it very well. The extra rpm's just seem to create more vibration and noise w/o any gain in performance on my large heavy war birds.
Going out this AM, will let you know the results.

Forgot to add, I am running AMSOIL @ 60-1 and this G-62 has about 25 flights on it (about 5 hrs.).