I don't think a first time guest would know what roads were busy or quiet when planning a route using a sat nav, they would just drive with what route it came up with.
As I said this is just my opinion, I think a sat nav is great for any other location.

Our directions also have photos and only have 3 turns before you arrive at the resort. So are very, very easy. Even a child could read them and not get lost. I have even included the correct toll money with a few guests who were really worried about driving.
[msnwink]