I've been using the Sigma Power ceramic 6k (aka jinzo renge suita) for several years, I'm on my second one actually. It performs better when you permanently store it in water and it doesn't have any detrimental effect on the stone.
Btw, the orange Select II 6k does have a binder. Not much though and it's very friable when used on soft steels. A small piece of Select II 6k also makes an outstanding nagura for the ceramic 6k.