Dave,

We have been using just plain old Master airscrew props with pretty good luck. I have crashed on them a few times and not broke yet. Except that one time I hit the new asphalt runway But other than that good luck. I did buy four grish yellow 9X7's off ebay the other night for $5 though. I should have waited.

We can't find these yellow props anywhere around here.
KsFlyer