Has anybody used the snow blower on gravel and slate walkway. Any thoughts?

I have used it on both and yes it will throw the gravel.  The issue I had was that I have river rock lining part of my concrete driveway and the blower picked up one of these about the size of a softball.  It threw it around inside for a bit but ended up breaking the scraper on the bottom.  Everything else held up, just the scraper broke.  This is most definitely operator error and I explained this to EGO when ordering a new scraper but they replaced it under warranty anyway.  So yes, I would say you can use it but just be careful.