RE: Saito is the best four stroke glow engine.
Scott, you say "only 17%" as if it were a bad thing. Frankly I think 20% oil is too much for the Saitos I've run. I've run as low as 12% full synthetic no problem, and lots of Europeans run their Saitos 10%-12% regularly, full synthetic. I think if one were to go up to 25%+ nitro you may want to up the oil content a bit. I do run 12% syn/3% castor in my Saitos for a little extra safety margin.