If IVDs were a concern I'd use Shell Nitro exclusively, but with a wet manifold and PCV modification my inlet valves will always be extremely clean.
I always use Shell Nitro because that's what was in the tank when the car was timed, jetted and rolling roaded, and it runs noticeably worse on any other fuel.
On the infrequent occasion that I can't use Shell, I'll only fill with enough fuel to get me to the closest Shell where I can use the fuel that provides the best idle/transition/power.