US fuel is different as it has a different rating system. Off the top of my head I believe that 91 is close to the 98 we use.
My car is achieving fantastic fuel economy, with average klms per tank getting up in the very high 500's (without the fuel light glowing when filled). I recall one mid to high 600's tank, but that tank had a few fair few highway klms. I would love to do an open road trip as I am sure 800 could be possible.
I am fairly good, maybe baby it a little too much at times. I find that it does not need a lot of revs to get the job done (however do not under rev). I must look at my average shift points, as I do it more by sound and feel than anything else.