Will be tight especially if the adults are near 6ft tall, I am & the front seat has to be about half way along it fore/aft setting otherwise the little one has no leg room (isofix Recaro seat) so I'm not at all comfortable in the front! Got an Altea too, thats not as bad, but wouldn't be easy with 2 boosters & a baba seat. Keep it VAG, Touran 140 tdi sport or if you prefer an estate, A4 130 tdi sport Avant (or 140 S-Line if you've got the bucks!), not mega room in the back seat though. But, its horses for courses & personal preferance aint it!