I gave a friend a quart of VR1 Synthetic 20w50 from the free after rebate earlier this year. It should be a lifetime supply for his blower!
In my Ryobi/Redmax commercial 26cc 4 strokes I've run straight 30, 5,0,10w-30 synthetic, Rotella 5w40, Amsoil 20w50, and T5 10w30 and couldn't tell any...