Right now, I'd honestly say to go with 156.55 (available at LaptopVideo2Go).
It's the first 1xx.xx driver NVIDIA has released that has full Mobile support (i.e. PowerMizer and other mobile goodies). I've been using it on my M1710 for the past few days, and I have no complaints at all. Just make sure you use the modded INF, and you should be good to go.
I'd also like to point out that there will be a MobileForce version of this driver coming soon, so keep an eye out for that one

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