By all means the buttons are programmable. You can assign any key to any gaming function. All games that I chose to play with the controller let me do this in the controls setup.
But, it won't let you simulate a mouse click in windows unless you download some kind of software people use to make that controller behave like a mouse in Windows OS. I forget the name of that software. It adds additional functionality to your controller's buttons. Maybe that's something you are looking for.
I found this -
http://www.instructables.com/id/Use-an-Xbox-360-controller-as-a-mouse/step4/JoyToKey-Basics/
As far as grip and feel go, this controller is great. Honestly, I have never used a rumblepad and it is also highly rated. Maybe someone else can comment on it. I am by no means rooting for the XBOX controller. It is what you feel comfortable in.
I had to choose a gaming mouse. I bought the two I narrowed down, and returned one. If you are in a position to do so, that's the best choice.