I bought my Vibe new in January '03, and it has been very reliable. I was horrified at first, when I leaned against the front fender, and it caved in like a paper bag, but the drivetrain is pure Toyota. I had a sensor replaced at around 100K for around $100, but that's it. I changed the hoses and serpentine belt, and flushed the radiator at around 80K, but that's it. My check engine light and airbag light are on, but it still runs great. It doesn't heat up until highway speed, so I think the thermostat is sticking. I am 6'3 and 275#, but I fit fine. My family of 4, and our luggage got 33mpg @ 80mph when the car was new!
Reliability and gas mileage! Roomy for a small car.
Terrible structural integrity. The body is like tin foil, and the plastic underneath the front, inside and out is falling off! I suspect I'll be driving only a chassis soon! Very noisy.