The best oil question seems to be never ending, no disrespect intended.
I just changed the oil my skylark 300, the reason being is the stuff was black, old and overdue for a change.
I used 10-30 Citgo (Farm and Fleet local label) & WIX 51258 and the and I am happy with the choice.
The chemical test for this oil as it is listed on the inter-web (search; is farm & fleet oil any good) and has good numbers
I would never use a Fram filter.
Nothing exotic here, except I keep an eye on the dipstick and when the stuff starts to look poorly, I change it regardless of miles, slogans, what your neighbor tell or anything else. Clean oil is number one in my book, zinc should help the cam.
I don't live is a real hot area (northern Ill.) but engine heat is always on my mind as an oil killer.
Using 10-40 could be a choice for hotter areas or worn engine, but that is just my opinion
Additionally, fuel contamination and general engine condition would be cause to change my oil sooner than later.
I have never had a lubrication related failure or premature engine problem that I could relate to lubrication, except for air cooled applications.
Keep it clean, your engine anyway!!
thanks for your time guys.