I think you should talk to your son about what he has in mind. Maybe you already have, but if he's picturing a funky little tent and then is faced with a big multi-roomed palace, then he might be disappointed? But of course, he might want the big one, with his own room - just better to be sure. I think the idea of two tents might work well.
But of course, we're all weirdo cyclists used to small tents, and other people do like the big ones! And I have to admit I have sat on damp days, watching people sit at tables in the 'living room' of their tent, and wished I was there instead of my teeny wee home!