Can you imagine anyone else playing the characters?

[Perny]

never.. It's impossible. we've seen them all through 7 years, and can't imagine other actors in their place. I mean... who else could be as good as James, Allyson, Anthony, Sara, and the others?

And...O.O The trio... They would never be that great with other actors!
There is only ONE Warren, ONE Andrew, and ONE Jonathan