I have both and I think you have to try both for yourself to decide. The automatic is brilliant in heavy traffic but makes me sleepy on very long drives . The manual when the clutch is perfect and you're not stuck in traffic worrying how long it's going to last , is the one I prefer on long runs plus it's probably about 10 mpg better on diesel
Don't forget the government will also rob you of an extra £100 a year for not changing gear yourself !