I don't know about everyone else but the Swellow I caught in Sapphire managed to do more work than my starter somehow and she pulled off several miracles involving Return, crits, and/or Double Team, so now I transfer descendants of that Swellow into every following generation. The status orbs coming into play in 4th gen was one of the best things ever.
I remember only keeping my Swampert around for Surf and Earthquake.
