Looks like a good place full of car nuts, I feel right at home

For a good few years now I have admired the Rs4 and got very close to buying one several times. We are in an F10 M5 which goes back at the end of the year and I am very tempted to buy a nice low mileage RS4, get a decent exhaust and tune on it and enjoy it as our family car for a year or two. What I am not sure if is whether the car would be large enough for 3 teenage kids? Anybody use one as a family daily and able to comment? I expect it will be slightly smaller and the boot too but in the real world I don't know how much the difference matters.
Cheers,
mondie