I agree with those that say you really need (at least) 2 bikes.
I grew up riding off road for 38 years. I still ride off road (some).
I had an xr650L and a Buell Ulysses , sold the Buell and bought my F800.
The XR650L can be a more capable off road bike then the F800. But if your only riding stone/dirt roads, the F800 can do everything the XR can (accept mud, but that is because you can get better tire selection for the XR).
I ended up selling the XR650 and buying a slightly used Husky TE250. The Husky is a much better dirt bike then the XR650 would ever be, plus its street legal.
But since we are allowed to all have our own personal opinions,I refuse to take my BMW somewhere that I can do major damage to it, while I would never think twice taking the XR or Husky into that same situation.
I figure why beat up my BMW trying to do something it's not really designed to do. Kind of like using a hammer to loosen a bolt when you know you have the right tool in your box.