I'd be jumping all over getting the LPG conversion ASP with a 50 mile a day commute! Making the figures simple (not necessarily entirely accurate but ball-park close enough) that's a gallon each way at 25mpg and £6 a gallon so £12 a day or £60/wk just in fuel. That's £3k a year to all intents and purposes!
With LPG about half the price of petrol, that's roughly £1500/year or £30 a week saving.
Glad you found another job so quickly too!