It's a comfort thing. During combat, I need the mouse to target properly so my navigation is restricted to keyboard controls. Outside of combat, when running around, it's more comfortable to be able to point where the ship goes and just have it follow the lead.
So the short answer is: if I had the hotkey, I'd change pretty often. Given that going into menus breaks flow, I nearly never do and stick to plain old WASD.
But as mentioned, it's really a comfort thing and won't make or break the game