This is the third year that I've had my LPG system, fitted by Warrington Autogas and Autogas99. Every year, from October onwards the LPG system is of no use, I've had to switch back to running on Petrol in the winter. This is despite repeated visits to the installer every winter (and more in between)
The system runs lumpy, fells like it's continually about to stall and often cuts out at junctions.
In short, whilst the LPG system is out of it's formal 2 year retailers warranty, (however, not out of the Supply of Goods and Services act implied "reasonable" period), it is now of little use for half of the year.
See here for the video of the car repeatedly stalling http://www.youtube.com/watch?v=aRV0ds4ijkU