Don't stress too much mate. Mines a 2013 ST manual brought it new and thought the same thing the economy was crap but it does get better as the motor wears in and you start to get a few mor k's on it. I now have around 20,000k's on it bullbar, roofbasket, dual battery, snorkel and power chip on it. Don't ask me how many litres per 100 because ive never been home long enough to see a fuel tank through it lately and work it out but from memory the last time i did see a full mains tank it was get up around the 1000k's. If i do this time home i'll let you know what it comes in at.

Cheers Shane