Went through 2 mice in half a year due to this... First was an MX518 - middle mouse button completely died halfway into September. Let's just say that warrany service here is shit (they told me I broke it >.<). Same thing seems to be happening to my deathadder 1800 now - MMB has to be pressed very hard to register, same thing was happening to the MX just before it failed. So any ideas for a mouse with lasting middle mouse buttons, overall good build quality and good performance (I guess you know what I'm looking for already since I mentioned an MX518 and a deathadder :>)?