Synthetic oils, especially amsoil are amazing lubricants. I ran my blaster at 50:1 for 2 years beating the hell out of it, and 3 dune trips where it was running the whole time. When it was time to rebuild the rings were worn so much they were the exact size of the piston. Nothing else was wrong, and there was almost no carbon build up.
Keep in mind you should go leaner on your oil to fuel mix with synthetics because they dont need as much oil to lubricate as well as petro based oils. However when you mix in less oil you then actually richen your air/fuel ratio. Many times you can drop down a main jet size and possibly a clip or a half clip (washer).