I have spent a long time on the LPG group and I am a trained LPG fitter. LPG is in many respects a far better fuel. It does not contaminate oil, after 20,000 miles your oil will be as clean as it was and because of the lack of contaminants it will not have broken down. One guy has his analysed after 50k and it was still not needing changing. Also it doesn't wash the oil off the bores, the combination of the two virtually eliminates engine wear. Not many people know this. Also it mixes easier and has a higher octane rating, bit like racing fuel. That means more turbo boost or advance/compression can be used. If with the new generation you can use liquid injection you will also get a bit 'charge cooling' effect and increase the power of the engine beyond what it would make on petrol. The old 'carb' systems typically run around 90% the petrol power, but smoother. The downsides are old 'carb' systems not well set up, some tank issues depending on where you intend to put it and also if the government puts the tax up. All in all I'd say LPG is a better fuel, but at the end of the day it's all down to tax. Which is why I'm looking for an E300TD TE to run it on vegetable oil which has a tax reduction. Mail me if you need any more LPG info, don't be put off by uninformed. However prices are way over the top, if you can't get a good price bear in mind how long it will take you to get your money back - the budget might start eroding the savings from now on.