I've been using a Razer Taipan that someone helpfully abandoned at my workplace, and while it's acceptable and meets most of my criteria, I have resigned myself to the fact that the Microsoft IntelliMouse 1.0 was just the pinnacle of mouse design and no mouse will ever be that good again.
My main complaint is that you have to run the bloated Razer software in the background all the time in order to make the buttons work as desired (it has 2 buttons on the left and 2 on the right; normally both sides are a copy of button4/button5, but I want both buttons on the left to be button4, and both on the right to be button5). With older Razer mice you only had to run the software once to program the mouse, and then the mouse retained that programming on its own, but apparently Razer has since decided that convenience is less important than saving 25 cents on the manufacture of a $50 mouse.
It's even more annoying because it required me to register an account and provide a bunch of personal information before I could even use the software; it does have an "offline" mode but you can't use it without registering and logging in first. Obviously I entered fake information and blocked the program from accessing the internet, but none of that should have been necessary in the first place.
However, if you like having buttons 4 and 5 on the same side of the mouse, or don't mind running bloated spyware on your computer, I would tentatively recommend this mouse.