Sorry, even though 4 strokes fire 1/2 as often as 2 strokes they actually run as hot if not hotter than 2 strokes. This is based on personal experience over the years and a hypothetis:

In a two stroke, raw cold fuel is drawn into the engine through the low end. The intake of fuel cools the engine's low end as it is processed into the engine, burned and exhausted. There is no low end cooling by raw fuel mixture in a 4 stroke because the fuel is directly sent into the combustion chamber from the top of the engine intake valave.

The only lubrication of the low end on a 4 stroke occurs blowby gasses containing unspent oil. Not enough blowboy occurs to actually have a significant cooling effect on engine, just enough to keep the moving parts slick and prevent them from seizing up.

A 2 cycle engine running 300 rpm shy of max lean can be touched for about 2 seconds before a burn occurs. A 4 stroke running 300 rpm shy of max lean will cause an instant burn if you touch it. Not very technical but observation and analysis are the most basic of scientific principles.

Coolpower 15% is 17% oil, 100% synthetic
Coolpower 15% 4 stroke fuel is 17% oil but contains some castor in same proportion as Omega (its the same stuff as Omega but different color0
Coolpower 20/20 contains 20% synthetic oil.

Omega/Coolpower 4 stroke fuel contain too much castor in my opinion for 4 stroke use. If you are a good needle tuner and run your engines lean and understand that an engine leans out in flight when you burn fuel due to differences in fuel tank head pressure than you can get away with using synthetic fuel in all of your engines.

I've been known to burn 2 stroke coolpower in all of my engines. For the 15% stuff that contains only 17% oil, I add 4 oz of castor to each gallon. When I burn their 20/20 in my 2 and 4 strokes, I add nothign to the fuel.