Back when STIHL and others were still rejecting synthetic oils, and only had 1-2-yrs warranty, ECHO with POWER BLEND OIL was offering 5-yrs warranty, and it was a few years before all others switched over. I SWITCHED to POWER BLEND FOR THAT REASON after locking a piston ring on a new saw w/ a carbon coat like a magic marker mark on 40:1 name brand dino oil while milling w/ new saw. A new ring and cleaning piston groove and back in business for DIY $12 piston ring, after a "Expired, No warranty" and $640 shop quote, and I still run that saw with ZERO ISSUES.
MY LOGIC was "Echo believes in their oil", so I took a chance, and I am convinced on synthetics... apparently those other skeptic MFRS are also NOW convinced?