I've used deathadder for about 1 year and the right click failed after that. If you are an extreme gamer i suggest not buying a deathadder as the buttons will slowly and eventually fail.
Recommend Logitech G9 or Alienware tactx
I've had my Diamondback for 6 years now (Gave to my cousin), and my first Deathadder for 3 years (Use with my notebook). My new Deathadder V2's buttons and casing are the same as my first, so I expect plenty of longevity.