I am building a new gaming pc in two months and need to decide on a mouse. I am pretty much stuck with Razer. Everything I have gotten from them has been amazing, so I want to stay with them. I will go into the reasons why I want each of them:
Wireless and Wired
Good for big hands (which I have)
Nice rubberized finish
Good for FPS
Great reviews everywhere
Love the LED's
I recently picked up a Razer DeathAdder because my last mouse died on me. It just feels very comfortable when it sits in your hand and I have big hands too. It serves all my gaming/media needs. I would definitely suggest the DeathAdder.
I took a look at the Mamba and it looks exactly like a Deathadder with 2 extra buttons and wireless. I would stick with the DeathAdder if I didn't need an extra 2 buttons, didn't mind having a cable (or rummaging around my desk looking for the wire connection when battery died in middle of something), and it's cheaper.
I can't say much about the Ouroboros. I would only get it if I am very (I mean very) picky on how my hand sits on the mouse (I find that DeathAdder fits just perfectly already in my hand).
i see no reason to get the ouroboros for a customizable mouse when there is the rat 7 or rat 9 if you NEED wireless. the deathadder is supposed to be pretty nice for fps. the mamba has extra software features i believe such as multible presents and on the fly dpi swithcing.