RE: Best stroller for travel (European),and carseat question
If you are going to be renting a car, then I would bring your carseat. Otherwise, maybe, maybe not. It is certainly more convenient not to have the carseat during overseas travel. As far as taxis go, I know this is unpopular, but we usually do not use a carseat in taxis when traveling. And most shuttle bus type things do not even have seatbelts, so it is a bit moot.
If I were you, I would take the Zippy. Even if it is damaged by the airlines, its not like its an irreplaceable stroller, KWIM? Many airlines will pay for broken strollers, although not all. If you will be doing a lot of walking in old towns and over cobblestones, you will quickly appreciate having a stronger, more stable stroller. As long as there are two of you, I wouldn't worry so much about the weight of the stroller. In fact, most Europeans have large, pram-ish strollers, because the streets are quite uneven and very harsh for babies in small strollers.
HTH,
Beth, mom to older DD (8/01) and younger DD (10/06) and always missing Leah (4/22 - 5/1/05)