The nice thing if you where using Stardog and this happened, you could easily move to any of its competitors which implement the same standards. Including opensource version too. i.e. you might miss a feature but at least your queries will still rung and you won't need to redo your whole app again.

SPARQL should really be everyone first technology to investigate before heading off to anything else. i.e. when you are still pivoting every week you should have the most generic database tech possible. Only when you scale you should specialize.