Problem with the Scion and other boxy little cars like the Soul is the mileage isn't very impressive.
I had a 2003 pontiac matrix(samething as the toyota Matrix) and it also made a good bike transporter. I don't know if the newer ones still do it but my old one was all plastic in the back which looks bad but it is nice when you have filthy bikes back there. Downside again though is mileage was just ok. Also still have a 2004 VW jetta wagon TDI which is a big car compared to most of the things listed so far, plenty of room in the back, and of coarse gets great mileage. Only reason I replaced it with my focus is the TDI is a automatic bleh. I got a screaming deal on it or I wouldn't have bought it. I need to get around to selling it.