I have been told by a couple of manufacturers that most 2 cycle air cooled engine runs best and happiest at around 300.
I have also talked with a few people that run telemetry in UAV's and the HIGH 300's are not uncommon on twins that we commonly use, though they like to shoot for 300.

Ralph, You mean the Evolution 26 is not as strong as the G26? That can not be[X(]