teleportation. u dont need the effort of flying an getting hit by bugs... u dont need to ever be late again... u dont get seen that often "look in the sky! its a bird, its a plane, its DrDoctor!"
the only downside i can think of is getting stuck in a wall and dieing instantly which would suck....
although if u cant fly u dont get a cool cape. :<
but u cant fly into a bank, u can teleport in , and then teleport out of prison..