I have been using the ASE 10-30/30wt for the past two seasons in all of my 4-stroke equipment with very good results. The UOA showed that the oil was still in nearly new condition after 144 hours in my ZTR with a Kohler engine (600+ hours).
I know the stuff is expensive, but, the results of the UOA give me peace of mind so, it is worth it for me.
Also, I use their Saber 2-stroke oil (80:1) with very good results.
Hope this helps.