Color - performance with nVidia Quadro FX 4800

I currently use the ATI Radeon HD 4870 for Color, which works perfectly. I'm considering purchasing Smoke once it's released for the Mac, and it requires an nVidia Quadro FX 4800 or 5600. Ideally I'd like to use Smoke and Color on the same box, and I'd rather not swap graphics cards every time I want to open a different app.

Does anyone has direct experience using Color with the Quadro FX 4800 or 5600? I know that the ATI cards have been the preferred cards for Color ever since it's been an Apple product, and I know that all bit depths aren't supported on the nVidia, but I only use float anyway so that's not really an issue for me.

By the way, weren't nVidia Quadro cards once the preferred cards back when Color was Final Touch?