That's pretty good! I can count using a single hand the number of times I saw 300 miles from one tank and I'm either on v-power or tesco 99! Having said that, I don't spend much time in 5th gear... Well done, that's not bad going for the old petrol. I also find tesco 99 quite sweet at the top end of the rev range, a bit more responsive at 4k+ rpm than standard, on par with v-power.
1.4SE Cobalt Blue, Koni FSD, Eibach -20, Pagid road front discs/pads, front+rear electric windows, Concert I, ICE-Link Plus (6 Disc Changer), Bose, Climate and leather