i've used both kevlar and wire beaded gatorskins front and rear in the 23c width for a few years now...They last a long time, they corner well, and they are pretty puncture resistent...
The sidewalls are dark dark brown with a lighter coloured diamond weave...
A lot of people talk about continental tires' sidewalls rotting out prematurely, but I've never experienced that with the gatorskins...The folding version is WAY easier to get on and off your rim and worth the extra money for that reason alone...