Hello Frank and Matt,
Frank, I would be very interested in the ST G20/15D, PM me if you want to sell it!
Matt, I have run the 5224 for many years and I must say that I am very fond of them. For a start, they run on no nitro fuel and don't seem to suffer for it. No vague needle problems here. I find that they do run on the rich side, but I seem to get more of a break than previous contributors.
As to the comparison with the OS 35 S, well these are excellent when new and do a Fox like 2-4. However once they are past their prime (and that isn't too much running time!), I find them prone to running away. My experience with rods has not been all that good either, they seem to wear very quickly. Given the straight choice I would go for the Enya any day, unless I had a draw full of new OS 35 S engines.
OK, I am a sports flyer, rather than a pattern flyer, so perhaps you should listen to those who do use them in competition. I have one of Brian's ABC set ups complete with rod, for the OS 35, I shall try it out next season. I suspect this will be better than either of the stock engines.
Regards,
Andrew.