I currently have a Thinkpad W530 with a Quadro K2000M. Because I have coreboot as its firmware, I am able to run completely on the discrete GPU. So far I've been doing great.
I've looked on the feature matrix of the nouveau support and my GPU (Kepler) happens to have all the features checked-off, with the exception of dynamic power management (mostly WIP).
Right now, I'm running KDE wayland with the nouveau driver with no issue.
On the other hand, I've tried having the hybrid GPU and it sucks.