I perceive Tom Hanks to be as trustworthy as they come.
Harrison Ford was the voice on a diaper commercial about 20 years ago.
Outside of the music biz, I wonder what Simon Cowell could convince people to buy? Can't you just visualize him selling used cars or something?
"Your car is the sorriest piece of junk I've ever seen. It's embarrassing. I don't know how you dare drive it without at least wearing a paper bag to hide your face."
"I'm not being rude, but the only thing that would improve your car is to set it on fire and roll it off a cliff."
"There's nothing here at Cowell's Classy Cars you can afford. Go away and come back when you've won the lottery."