I always encourage clients to set up their company email with Google. The best reason I can come up with that is both practical, but also instills an element of fear into the decision-making process, is that the free email service being provided by your shared host can cause problems that are far out of your control. Unless you actively purchase a plan with a dedicated IP address, the introductory shared hosting plans most people get, will require them to share a single IP address with other users.