A good MPV with low roadtax

I am thinking of getting an MPV (5 seater). A 2008 model with a 'B' in the CO2 rating would fit the bill. Am looking at trying to save as much money as possible and would look at getting one in the UK.
Am looking at the Renault scenic. Does anyone have experience of this car. Any other reccommendations for a diesel in the B category MPV's?