"The most extreme case in point is Maya, where the FirePro V8700 is six times faster than the Radeon HD 4870"
Surely the fact that even today the cost of the FirePro V8700 is approximately 8 times more than the cost of the HD 4870 makes the performance comparison completely irrelevant. (unless you have an overwhelming need to buy a particular piece of hardware regardless of cost)
If u are working with wireframe, thousands of models milions of polygons u better of with quadro or firepro, they simply will give u 100 fps or so in viewport where GTX/ gaming card will give u 2 fps.. thats the difference, But now GPU rendering is coming to the market so be aware of spening £5k on graphic card...
Could you more specific please. I am not looking to generalise all workstation cards and compare to all gaming cards. If you could give an example based on cost that'd be really helpful. Even if you take the £5k mark. What performance will £5k worth of gaming cards give you in comparison to £5k worth of workstation cards. Actually test results or past experience rather than opinions please.