Two years ago I had bought one for almost €90 - €89.99 -, the Logitech 604 Lightspeed and it was fine, it had and has many buttons, it is comfortable, etc., but it didn't last me even a year without issues.
So I got tired and decided to get what is probably the cheapest wireless programmable mouse that exists but it has good reviews, and it also has 16 buttons. It's great because it makes it easier for me, especially for certain games.
The reviews I've seen of this mouse are not bad, and that price for a 16-button programmable mouse, €29, it's not expensive. If it breaks in less than a year like some of my mice before it wouldn't hurt so much.
I like this type of mouse, for RTS - selecting groups quickly - and for everything in general.
Those extra buttons help to map kb keys to the mouse and use the kb for moving and stuff that don't require an immediate action.
The mouse is the E-YOOSO X-33 wireless.
There are reviews on it explaining its virtues and flaws.