It really comes down to who I want on my team and who's most suited for it of my choices, since it'd be a pain to switch at a PC every time I wanted to fly somewhere otherwise. In White I taught it to Kokoromori, and later deleted it to take advantage of the ability that doesn't let it take advantage of held items, thus making good use of the move "Acrobat". I instead taught it to my Mamepato (now Hatoubo), and later Wargle, and I may eventually delete it from Hatoubo. Someday, if Latias is ever made available, I may teach it to her since I know I want her on my team and she'd take precidance over Flying types, but then I'd also feel I'd be wasting a move spot since it wouldn't even take advantage of STAB.