The Volkswagen Golf 2.0 TDI R-Line DSG Euro 6 (s/s) 5-door is an excellent all-round choice if you: do significant miles (especially on motorways), want a premium, well-equipped hatchback that is practical and refined, appreciate the balance of decent performance and diesel efficiency. If however your usage is mainly short urban hops, low annual mileage, and you prioritise ultra-low running cost/lowest emissions, then you might consider whether a petrol or hybrid version might be more appropriate.