for a long time i used morgan fuels sidewinder 30%/12 % oil, then backed off to their 20%, using the exact same tuning procedures i use now, i was having lots of engine bearing issues( pitting of top of piston, going through glow plugs) must of replaced 3 or 4 ebay blocks with bearings, switched to either traxxas top fuel or morgan fuels backyard basher brand with 16% oil and voila, bearing issues went away, from that, i figured since i have never burnt up an engine, broke a rod, or any thing else catastrophic, it had to be oil content, everything else being equal, so thats my opinion on fuel......
P. S. since i dont race, why not get the most lubricative fuel available, to protect my investment?