SS heavy vs Logitech g640

Hey guys, i am about to buy a new mouse pad. I got the mouse SS Rival (first version i guess). Can anyone tell me about their experiences/ differences they maybe noticed between these two mousepads.. I currently got qck mass; its nice i guess; but due to time it got kinda worn out and also there is a small bump that i regularly feel while playin though (cs go) not sure if this will happen with ss heavy again..