^ Exactly. There will be no compatibility issues. The only ones that could occur is if you force modifications to the game (i.e. profiles intended for other games). Example: I set an anti-aliasing flag of 0xF0C1. Well that flag is for OpenGL primarily, and idtech4 and below. Either performance of the game will suffer immensely, or nothing at all will actually happen...it may actually work better than the ingame anti-aliasing too. You will not incur more instability and crashing than what already exists. The only time inspector is running is when you open it up, it takes up no resources. When you close it, its closed and finished.
Like tet5uo said, everything in inspector is already in the driver, so I'm telling you to do that. I can assure you it works fine. Many of us do this--I even set it up time to time for my non-tech friends who are pains, and won't try to learn this themselves. My reason is the same as tet5uo as well, I have a 120Hz monitor, and a lot of games the extra frames aren't needed, or drops can be drastic.
Anyways, driver side is always more effective than what a game can do.