I have one and its great, Ive been a passenger in the 140 diesel and in my opinion, havent seen much of a difference in the sprint.
I averaged 38MPG from Oxford to London, but on country roads can be luck to get 30.
I would be lying if I said mine was reliable. I got it in August, 43k Miles and within a few weeks it needed a new Fuel Pump Contorl Unit, Throttle Sensor, Electronic Control Module. The AA warranty didn't want to know, but the dealer I got it from (VW Petersfield) were happy to take it back and shell out for the repair. Only downside was being Petersfield was a bit of a drive away.
Next had a Ignition Coil go in November, which the AA warranty did cover (although as you might have seen, there is a current recall on the Ignition Coils).
Last month I had a new EGR Valve and Coolant Temp Sensor.
Oh, and the radio also turns itself on when it goes under 0 degrees! Local VW dealer we get on well with has said I've just been unlucky. Hopefully thats the the end of my problems!
After all that though, I still love it. Its comfortable, quiet, yet is great fun when you want to play!
