I, too, have one – with a car I drive about 15 minutes along the innermost “ring” road whereas any combination of public transport would require at least an hour for the worst case scenario. Yes, the trip takes longer in peak traffic; luckily I can avoid those times most of the time – and it's in any case way faster than with public transport.
It was comparatively worse when I had a much shorter commute to school years ago. The 3.5 km trip would consist of more than a kilometre of walking and would at worst take way more than half an hour with buses (including the switch, without one you'd have to walk more than half the distance). Needless to say, I did not prepare for the bad days, and was late quite often.
With a car, it was literally a five minute ride.