While GeForce Hotfix driver 355.80 is not certified, or even beta, I know that a lot of our readers have issues with SLI in Windows 10. Especially in games like Battlefield 4, memory usage would expand until, apparently, a crash occurs. Since I run a single GPU, I have not experienced this issue and so I cannot comment on what happens. I just know that it was very common in the GeForce forums and in our comment section, so it was probably a big problem for many users.
If you are not experiencing this problem, then you probably should not install this driver. This is a hotfix that, as stated above, was released outside of NVIDIA's typical update process. You might experience new, unknown issues. Affected users, on the other hand, have the choice to install the fix now, which could very well be stable, or wait for a certified release later.
You can pick it up from NVIDIA's support site.