We had a mixed experience of the Paris metro. It was very very hot, but so was the whole of the city. Sometimes the tickets wouldn't let me through, resulting in me buying a second ticket on one occasion, rather than ask for help. To be honest, at a quid each it didn't matter. The machines selling tickets were a bit weird, but I grew to like them, especially when they said 'code bon' after I entered my credit card's pin. The signage and maps were okay and at their best when most closely like our own. So, so far you'd be left ambivalent. However, the sheer scale and efficiency of the service left me impressed in a way that wasn't impressive last night. So boo to London and Yay to Paris.