Civic 1.8 is a lovely car (I've got one) pretty quick off the mark and feels about twice as powerful as the Jazz and with 6 speed box. Lets you overtake without having to plan miles ahead and more comfortable on longer journeys, but is a lot lower than the Jazz, also more choice of tyres with 205/55 size, and cheaper than oddball 185/55R16 on Jazz.
Steering on Civic is a lot sharper than Jazz, seems to be about 1 turn of steering wheel takes you from lock to lock, whereas on the Jazz it feels like 3 turns, I have to get used to this when her indoors makes me drive her Jazz, I do miss the tight turning circle on the Jazz though, makes it a lot easier on carp arks.