[apyrgiotis]

(disclaimer: one of the Dangerzone devs)

That's something I do from time to time as well. AFAIK Google Drive renders all documents on the server-side (which implicitly means that they don't trust the browser sandbox), so that's a reasonable price to pay for less privacy.

Dealing with sensitive documents though is another story, you just can't upload them to a third-party service. That's where projects like Dangerzone come into play.