I use Valvoline 2 stroke oil because I happened to get a deal on a couple of litres of it years ago and I haven't run out yet (I'm not a 2 stroke enthusiast). It has been very good to me: I have used batches of mixed fuel based on this oil that I've kept for more than a year, and it has apparently been as good as ever. Remember, though, that I was using petrol with no ethanol at all, and Australian petrol does not have some of the other nasty additives common in the US.
Long, long ago I used to mix up petrol and (new, clean) engine oil for 2 strokes. It was a pain in the backside, because it didn't stay mixed and it also caused formation of carbon whiskers across spark plugs. I would not do that again, or recommend the practice to anyone.
I stick to the engine manufacturers' recommendations for petrol to oil ratio. I have no respect for oil manufacturers' opinions on the subject. Yes, there are additives that can make it possible to use a bit less oil in the mix, but the engine manufacturers know that and take it into account. When I was a lad we had to run 2 strokes at 16 to one, and the guy running the mower ended up as smoked meat while still on the hoof. Most modern engines are developed and approved by the manufacturer to run at either 25 to one or 50 to one, depending on how they have designed the engine. That is way better, and while there is still a smell problem, there is no longer much smoke.
