I'm using 2 at the moment.
20" Zildjian K Custom Dry Ride
20" Sabian HHX Groove Ride
Dig both of them very much, always trying out others and taking suggestions for new rides. I really want to give the Evolution ride a try, I've heard great things about it and have had some great experience with other models in that line (crashes, splashes, and the Ozone crash all are great IMHO).