>>58856396Experience rate.
Pidgeot is just easier to level up.
Also in FRLG (the most popular game where this comparison has a point) one can make arguments about Feather Dance vs Mirror Move, but ehhh... both are gimmick moves.
Overall there's a lot of Kanto flying-types to choose from. Pidgey and Spearow are quick to capture and very useful in clearing Viridian Forest but obviously there's a lot of better Pokemon.
