Originally Posted by
wjm457
it depends on where you're going in the city.
This. There are many journeys where the tube is faster than HEX, and there are many journeys where the travel time is close enough to make the cost difference silly (like spending £1 per saved minute, which is about the marginal cost of HEX on this trip).
For this journey I'd take the tube 7 days a week and twice on a Sunday.