So If Christine, Stevie and Lindsey were to bring in one existing solo song..

[KenB]

For Lindsey, the correct answer is clearly "Deep Dense."

Among those suggested by others in this thread, I'd also like t hear GOS or Gone Too Far done with Mac.

Trouble already sounds like a Mac song. No need to make it one. (Although I would like to hear the Mirage rehearsal of this song that someone else said exists.)