I will definitely second the idea for using pregens at a convention if you want to concentrate on playing the game instead of just building characters. Convention games usually have a strict time allotment. Using pregenerated characters also allows the players to be involved in the scenario right from the start with prebuilt hooks...
"Those rotten bandits stole my sister's ring!" "And my horse!" "They are also led by an old enemy of mine." "I recognized one of them from the long scar on his face, he is an evil man who has cheated many."

"Let's GET THEM!"

There you are, off to a roaring start in less than a minute!