360 HP estimate???

Not sure on the ratings tbh, our worst stuff is normal unleaded 95ron. I have no experience of running N20 with todays fuel, N20 doesn't care how good a fuel you use but timing will be the key to stop a disaster happening especially with "clean" jetting tunes. Very hard to say what fuel he should use as it depends on the motor combination which is really what makes the power as to what fuel to use with how much timing and N20, generally premium with perhaps some additive would help of course. For a small 125 hit you could use just 2 or 4 smaller fuel jet with only a few deg. retard depending on fuel rating and still gain 6>7ths or more today. Wouldn't think you need anything like 100oct for a 125/150 hit.