I don't have experience with Office 365, but GSuite has been transformative. I never want to go back to mailing files around. Furthermore, while you'll always have power users who need Excel or Word for some reason, in general, GSuite for me has pretty much everything I need and it's far more streamlined. It's very rare that I want to do something--other than when I need to exchange Word files--that I can't do with Google (and even then I can usually work around it).