I got a little over 200 miles on £40 of LPG
Excellent as a daily runabout and without doubt one of the best made cars Audi have ever released.
Loses a little poke on LPG but above 5000 rpm the engine kicks over to petrol and you have no idea its doing it apart from the additional boost of power.
Its not quite as quick as my E39 M5 and that did have a better chassis; but the S8 is much better made and better mile muncher. Also its a little quicker than my D3 4.2 in gears but looses out a little as it has 5 instead of 6 ratios.
Saying that the gearbox is a honey as its only done 10,000 since the people at Mackies did everything on it.
400 miles in 5 hours back from Scotland last weekend was dispatched with an ease that nothing I have driven come close to (though I admit that's mainly been work hire cars including Mondeos/ Insignias/ Lexus IS/ Golfs etc).