"There is a small set of specific hardware features that the Quadros
have that the GeForces don't.... In general use you don't notice them being missing.
There is one (other) potential feature of the Quadro that would make it superior to a GeForce. That is in its memory management. The Quadro is advertised as having a special set of code for dealing with large objects that consume most of the memory on the card and for dealing with multiple GL context windows...
Now the above is irrelevant for 'Hardware Rendering' in Maya since you never render (or playback) two different views at the same time.
Where could the difference actually matter? In Maya you often have four different views open... for editing your scene.... If the (model) is large and really hammers on the graphics card (during the editing process), that is where you should expect to notice a difference between the two cards (in terms of performance)."
I was actually thinking about getting ATI X1650 Pro 256Mb
If you don't get a quadro, get something like a 6200 or 7300. I used a 6200 for Poser and it worked much better than my current 7600GT. I think it's some compatibility issue with OpenGL... But either way, a card like an x1600 is more for gaming.