Hi, Gerald. Thanks for the good words!
I ran all my 4 strokes on 10-22, 50/50 castor/synthetic for nearly ten years and never had a problem.
This was everything from the OS 20 up to the SAITO 90.
At the suggestion of Bob Reeves (THE 4S specialist), I recently tried 20-20, to which I added just enough castor to bring it up to 22% total lube (for bearing protection). It's now my fuel of choice. Although I was pleased with the original 10-22, the newer mixture seems to bring out the best in the engines. A bit easier starting and much easier to set the mixture. So far, I have only tried the 20-22 on the smaller engines but soon, I plan to do a bit of testing on my SAITO 56.
To this day, my all-time favorite stunt combination is the SAITO 30 in the ARGUS.
Also, Bob suggested clunk tanks - talk about an improvement! I now plan to use them exclusively, in all my planes. Watch for an article in the next CL World.
Bob Z.