VP C85 vs E90 pump

My local E85 tests at 90% every time. For a mile event, would it be good to use the VP fuel, or is the pump just as good when it tests that high?

I assume no tune needed if I run the straight C85?

Not really thinking about power increase, more a safety factor.

Thoughts?

c-85 is very expensive!!! e-90 you should be fine! C-85 is supposed to give you a %5 gain over e-85. Your ecu should accommodate both very well!