I would not use the "break in fuel" use the same fuel you plan on using forever. I would recommend the race blend even if you do not plan on racing. I get lower temps with it. A lot of people do not use the race blend because it has less oil. I find the fuels with more oil are harder to tune with and I get higher temps. Sounds backwards i know. But that is just what I have experienced myself.

I run nothing less than 25% nitro in all my nitro's. You hear a lot of people say your engine won't last as long and so forth. I know a quite a few people that will tell you they will last the same. Because everyone in my club has used both - the lower % of nitro in some RC's and higher % of nitro. We find the life of motor doesn't change enough to worry about it.

Any - take for what it is, Just My Opion (JMO).

Cheers, Hope it helps.