My driving profile has changed markedly since buying my second Mk8 this year. It is now four years old and on the original battery. The car spends three weeks of the month largely dormant doing no more than 100 miles and the fourth doing about 1,000 miles in four stints of about 250 miles a day. At the start of the week, the car will not keylessly unlock from the passenger's side but by the time I have arrived in Carelles 300 miles away, it will and the stop start is active within half a mile, remaining so for the rest of the week. Regular long trips are the key to good battery health. Using the performance tops the battery up faster. A good thrash from Poole to Chichester is enough to enable the stop start as a rule.