Diamond Rose's Green Elvi is my vote.
My reasoning is that that smallest piece I work with is a finished 1/2" and at that size I would STILL see a whole green Elvis head floating in my quilt - shudder the thought. Great. now I'm going to have nightmares of a bargello with a wave of green elvi heads moving up, and down, and up, down, and up and (speaking of up - here comes dinner).