I use 10W-30 and 30WT all in one.
For those that cant figure out how amsoil does this it is because the REAL synthetic group IV and V base stock they use is a straight 30WT but it is so good it actually flows like a 10W and meets the requirements to be labeled a 10W-30 and also straight 30WT. They don't add any viscosity modifiers to the oil at all. That makes it a superior oil because viscosity modifiers make oil less sheer stable and less stable in general. This is very important in these hot running high load air cooled small engines. The oil does not sheer out of spec as easily and it does not break down from the heat as easily as fake synthetics. On top of that the amsoil i posted is high in detergents and high in ZDDP which is great for the flat tappet cams in these small engines.
All 10W-30 oils bought at parts stores are fake synthetic and most people don't even know it. Group III base stock is not real synthetic. It is crude oil that goes through a process (hydro cracking) to make the molecules more even (simulate real synthetic).
Now take that information and do with it as you like. I know some people are set in there ways and refuse to make any changes. That amsoil can easily go 200+ hours before it should be changed in these small engines assuming you run a quality filter and your air filter seals up tight and does a good job like the big donaldson air filters do.