My opinion,
Get the next to latest driver.
I seen or recorded no measurable difference between drivers of the last few months. Nvidia releases a new one every month or so, so keeping track of all drivers for all GPUs is a tedious (and useless) job.
The first drivers needed some tweaks, and occasionally you got a bad apple.
The newest drivers sometimes come out with errors (non folding related).
I'd stick with the 2nd latest stable driver,as there are no real benefits in the newest driver for folding or crunching, and the newest driver occasionally gets pulled.