I always have, and always will use a Castor based oil.
Any oil that is designed for air cooled motor cycles, but not for weed eaters or chainsaws.
Choice of oil is an operator preference, one will be informed by a multitude of people that the oil they run is the best.
Provided it is mixed at the correct ratio, and the jetting is spot on, then any good quality 2 stroke oil is the best.