Asking what is the "best" oil is like asking what is the "best" religion. It depends on who you talk to.
How much oil also depends on if you replace the filter or not, and where you live.
I have no idea who would change oil but not replace the filter, but if you look in the service manual they give you the numbers for both.
The service manual calls out 1.48 US qt, 1.40 L, or 1.23 Imp. qt (with filter change)
I have been using Amsoil which is really expensive relative to other oils.
Many people swear by Yamalube.