The whole point of the FF is, of course, bringing a bit of practicality to the 1% who've been burdened by too-small backseats and not enough cargo room to fit more than one golf bag and maybe a cosmetics case.
The FF's back seats aren't enormously roomy but they at least don't make your passengers feel like excess baggage. Slightly raised up, they even offer your kids a decent view out the windshield.
The cargo space in back is, similarly, bigger than you'd expect in a Ferrari but not really bigger than you'd expect in most cars. I was told you could fit two golf bags back there, but I think you could fit more, provided you're willing to stack stuff on top of your golf bags.