Gatorskins are a little stiff, I think. My most recent tire is Michelin's Krylion Carbon. Supposed to be flat-resistant but maintains most of the feel of the Pro Race series, which I like. It's fairly light also, not too pricey, and available at probikekit.com, and biketiresdirect.com.
http://www.probikekit.com/display.php?code=Y2052