Any mouse that uses a 5600 DPI laser uses the exact same Phillips Twin Eye laser. There are some minor flaws in the tracking for that laser. At max DPI it fails to track very small movements accurately. Theres also problem with lifting hte mouse where the cursor would drop sharply down every single time.
I personally used two mice with that same laser and they never worked out good for me since I max out the DPI. Only when I learned that everyone was making mice with the same 5600DPI laser did I switch to logitech.
Logitech mice use their own laser without any of that problem. The G500 and G9x are very good mice, they have the same laser but with different grips. I personally prefer the G9x but both are good. I particularly like the weight system on them.
I never tried the Mionix so I can't say anything about the laser.
I do recommend the SteelSeries I2 mousepad though. It is all glass and glides incredibly smooth and doesn't wear down like beaded plastic surfaces.