I had/have the third row option in my 07, 11, 12 and it is very handy. The space is small but It is mainly for kids. A full car seat will not fit but a booster seat with the back will just fine. I had a full car with luggage one time for a short 20 min trip and it saved us huge, 3 adults and 5 kids plus suitcases...

Some scenarios which I never thought would happen but was saved by the third row.

We were at Ikea and the wife had to have some book case(70 inches long) for the kids play room. I put one kind in the third row, one kid in the second, folded down 1/2 the seats and every thing fit like a glove.

Boys would not stop fighting in the back seat (45min left in the trip). Just pulled over, threw one in the third row, and BOOYA no more fighting.

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2012 X5 50i ZAP(2VA, 336, 465), ZTP, ZPP, ZPS(6VC), ZCW, ZRC, 322, 4UB, 4NC, 610
2011 ///M3 Silverstone II
2011 X5 50i(lemon)
-- SOLD --
08 550 Msport
07 X5 4.8I sport
04 545i sport
02 4.4i sport
01 540I M/sport
00 SL500
97 SL500