Former xB owner here, wrecked my '06 last year. I would buy one again in a heartbeat if it had low mileage.
LOVED that car. sure, the cube may not be for everyone, but that shape gives you a fantastic interior. The high-angle windshield makes the cabin feel huge, and you can fit quite a lot of stuff in there. Pretty good gas mileage, though they put a bigger engine in for the '08 (?) redesign.
Very reliable, very practical, very good car. Especially at that price.