Personally, I hate to leave seats folded down. then there's the issue of things being on display. Not an ideal situation. Besides, if you need extra seats/space, then surely a bigger car is needed rather than a samrt. Plus, in europe at least, toyota have the Aygo, which is a 4 seater with a boot, not very big, has the same 1.0 engine and handles very well. Plus its mega cheap at around £7k (about $14k)
Don't get me wrong, the way toyota have engineered the iQ is amazing, but I personally wouldn't have one. Too expensive, and in the UK, we have the 500 which looks cool, or for not much more the Mini which will go much better and hold more value