Exactly I may go further than all but the diseasel drivers, but it still doesn't really mean anything when my MPG is worse. Currently I'm on 54 mpg indicated so about 52 in real life. 54 is the magic figure I need to hit to get to 500 miles so I'm hoping to do that during the summer. 500 miles would be pretty cool on one tank in such a small car. Still not as good as my dearly departed scrappage 406 which would do 630 miles on a tank of diseasel.
This year when we get the warm weather (don't blink and miss it) the 500 will do better than last year as she has a few more 1000 miles on her so you should improve.
And h ow big was the tank on your french tank ?