I had a fresh install of 13.10. The graphics were laggy and it was crashing when I was changing wallpapers so I went ahead to install the latest Nnvidia drivers. (it was using some generic one before that).
I followed a tutorial that had me add a PPA rep and install it from there. All went good but, when I restarted; Ubuntu doesn't load but gives me a blank black screen after I select it from the boot menu.
P.S.
Here is the tutorial I followed.
You can uninstall the driver: How can I uninstall Nvidia proprietary drivers? - and then install the one from the repos (you can use the "Software & Updates" app).
"All went good but when I restarted" = all went good until I tried to use the driver.
You shouldn't be surprised, even the tutorial you mentioned says "they don’t risk uploading a piece of software that has yet to be proven stable". If a driver is available in the repos - it means it is generally safe to use. If a driver is made available by the vendor - it could mean anything: from "tried & tested" to "go & try & mess up your system as you like".
