Plantronics DSP500 Surround provide great positional audio with drivers on in game mode(that kind of sound that you can even follow throught the walls)

i wonder if Sennheiser PC161 provide the same or even better since they're analog using an onboard sound mobo Asus P5K-Pro Realtek HD
what you think?

I don't think the 161 has that directly, as I think it is implemented on the USB soundcard that is an integrated part of the DSP500.

However, the USB version of 161, PC165 might have the same system... At least I know that the PC350 has it, but those are a bit more expensive.