disc brake question

hello.
after using hayes for a number of years, it's time to try something else.
This time I want a hydraulic disc brake that doesn't make that little
"tinging" drag noise (ya know the one I'm talking about?). No matter how hard
I had tried the brakes exhibited some amount of rub under various
circumstances (ie pedaling while standing). If only I could just ignore it
everything would be cool but I can't. So my question is, what brake is
best in terms of setup and tolerance between the pad and rotor? For me I
think the problem is amplified by that silly Trek disc mount system (a
mount that bolts onto a mount == very flexy brake mount).

thanks
neil