Fisherman,
If you are runing the idles that rich and still getting high temps, I would really start looking for an air leak. Check your fuel line first. Check for leaks around the carb, needles and the base of the cooling head. The best way to do this is by getting some nitro cleaner and spraying it around and on these parts while the engine is running. If the engine dies when you spray a certain part, you have an air leak. My engine had an airleak and this was the only way to find it, and definitely know where the leaks were.
Back to the best fuel ... there really is no best fuel, just "better for you." I used to use Trinity monster 20% in my CV-RX but switched to O'donnel when out of curiosity. Seemed to be much better, smelled funny though (the exhaust). I then started racing and everyone swore up and down about Byron's. I was lucky that my LHS carried it. I use it now and love it to death!. Burns cleaner and performance is great, after retuning my engine.