Synthetic,
I have the same combo Quest/YS110. When I bought my 110 from Central Hobbies they recommended a 14x11 for break in. Only 1/2 gallon through it but turns 9500 rich on 20/20. Good speed but a little more thrust would be nice. I ordered a 15x8 and a 15/10 to try. You will love that engine. Plenty of power for the Quest.