I personally run Team Losi Nitrotane 30% Race Formula and have been very pleased with it. I used to run the 20% Race Formula and made the switch last indoor season. I felt a slight power increase with the 30%, but nothing drastic. A lot of people say 30% increases engine wear, but I had 18 gallons on my first GRP without doing any maintenance. If you feel you need a little more power, you can go to 30%, but it isn't that big of a deal in my opinion.
CJ Weaver