bahhh 300 miles from a full 19 gal tank isn't so bad... although i wasn't impressed. Do you rev it up high once in a while? or is this the result from revving 3000 and below only?
Either way it cant be worse then american cars...
3.7 v6 engine from an American car would probably be at the most 200 and average 150 compared to the Z's 300 average.
This is how I make myself feel better.