I've done 100k in an Octavia 1.9 TDi, 110k in a Mondeo 2.0 TDCi and have recently gone for a Civic 2.2 CDTi. In all areas but one the Mondeo was better than the Octavia – better handling, faster, comfier (the Octavia I had had seats like concrete). Where the Mondeo fell down was after 120k bits started wearing out and it became costly to keep running. Still drove very well but I couldn't afford to keep it (ask Mondeo owners about dual mass flywheels).
It's early days for the Civic, but first impressions are: good practical load space, looks great, very refined for a diesel, ace panoramic roof, very nice seats and a cool dash. The rear spoiler does has the advantage of hiding headlights, but in an ideal world I'd manage without it thanks. I think the suspension is ace. Yes, it's a tad harsh on the potholes, but you forget that when you're tanking around a corner and it seems very well damped. It's fast in a "don't realise how fast you're going" kind of way, but so far I'd say the Mondeo was more fun and involving.