I started out running APC's. 16X10, 18X6W, 18X8N, and 18X8W. The 18X8W was best, but the plane was just to fast, and had little braking.
I then went to Zinger wood props. 18X10, 18X8, 18X6-10, and I currently fly with the 20-6 cut back to 19.
I would recommend experimenting with different props to find the one right for you, and your environment. It's more pilot preference than an exact setup. I have friends flying the OS 1.60 with the APC 18X8N and 18X10 and that's what they prefer.
You should really like the Extra! I started out with the 27% CG, but have been slowly moving it back to find the right spot.
Have fun!