I voted no on the elastic. I just got one of the Bellwether Crit Jerseys, which don't have the elastic, and it feels so nice! It's snug enough so it doesn't flap. But I do think it would be improved with the grippy stuff around the bottom, to anchor it a little more firmly.
2007 Trek 5000
2009 Jamis Coda
1972 Schwinn Suburban
"I rejoice every time I see a woman ride by on a bike. It gives her a feeling of self-reliance and independence the moment she takes her seat; and away she goes, the picture of untrammelled womanhood."
Susan B. Anthony, 1896