I've had 2 Seat Alhambra's (first was nicked), been really happy with them and totally reliable (though aircon had gone on the first one: and never got to find out if it just needed a regas as it was nicked before I got round to it).
I recently picked up an '04 130bhp diesel SE (top of range) with 60K for just over £5K. Does an easy 45mpg out of town. Nice drive (think the SEs have a stiffened suspension).
Rear seats removeable (but heavy and bulky to store) to give a huge bootspace. Loads of passenger room and all 7 seats are adult comfy. All 7 seats are separate as well (not bench seats): helps to keep the kids that bit further apart to avoid stray elbows!
Zafiras smaller, middle bench seat & rear seats only really comfortable for kids but do rears do fold flat into floor.
When we bought our first Alhambra a few years ago the Seat's were cheaper then the Ford Galaxy: now its the other way round as Seat's image turned around with the Leon etc. Galaxy's fairly cheap looking internally, Sharan's ugly & expensive, I much prefer the Seat's.