Popular opinion seems to be yes, they do. But....it seems to be that intakes are of use higher up in the rev range, but may offer less benefit under normal driving circumstances. I'm ready to be corrected!
I'm about to have a Revo fitted along with all the other required hardware for stage 2 so I guess I'll find out soon enough. I have track days in mind for mine.
What I have read recently seems to indicate that there can be fuel delivery issues in as much that on some cars when stage 1 mapped the pump can't necessarily deliver what the ECU asks for, particularly in mid range. Changing the fuel pump deals with this and helps release some more power and probably smooths out delivery I would imagine. I think if I were to settle at stage 1 I might buy an uprated pump of one brand or another instead of an intake.