RE: Fuel Used in Gas Engines
The higher octane rating means the combustion heat/pressure can be higher with higher ratings. Power remains about the same. Preignition starts at a higher temp/compression rating with a higher octane rating. Regardless of what engine a higher octane rating will give a little more room for a lean hot running engine and or help the engine run on hot summer days.
Most engines will run fine on regular gas. The extra octane is like a bit of insurance. That said the high compression engines, and I'd include DL in there will be less likely to have preignition/detonation with the higher ratings.