I think 1nc2000 as well as another member, nailed it with "depends on your application" not the answer we want to hear, yet to the point.
1) ambient temperature
2) boost #'s
3) conditions
Three riders
#1 goes 40mph all day with the occasional blip to 100mph
#2 trail hound who's in & out of the throttle all day
#3 ice drags or event, etc.
#1 probably won't need boost additive or larger i.c.
#2 IAT's never get a chance to cool down, where a larger i.c.may help to control things a little better.
#3 might just need some octane additive and cool downs between runs.
Point is....go do you, and find out what your particular needs are.