It arrived today.
I have to say it is a pretty decent upgrade from the MX518.
The MX518 was very good imo, it had great intuitive DPI and overall I couldn't play without it.
The g500 has the same grip type and even has additonal buttons. (not too many)
I also like the very rough coating for it, making me have more grip. The design is pretty sweet too.
You can also 'unlock' the scroll wheel, making it loose and thus allowing you to scroll very fast. The scroll wheel can even go left and right, so you can scroll left and right, never seen that on a mouse.
Assigning macros to the buttons is also sweeet.