I'm pretty sure this feature is not available, but when running dual amps from the POD into a stereo setup - if you could add a delay to one of the amps (5-20ms) so you get a more stereo feel and sound coming through the amps. This sounds really great with palm muting.
I'm not talking about adding a delay pedal, because that wouldn't work in this case. I would of loved to see this on the 500X