I've had my Yaris for about 3 months now, and have had absolutely no problems. I love it. I live in DC and it handles like a dream and is easy to park in a notoriously hard-to-park-in city. True it doesn't have a ton of features, but I wasn't looking for that. This isn't a 'starter car' for me, but I would recommend it as a first car for anyone. I wanted something economical, but didn't want it to look or feel that way. My friend got a Honda Civic the same week I got my Yaris, and all of our friends like riding in my car better. :)
I really like the speedometer in the center, as well as all the cubbies cupholders, and glove boxes. Love the fact that it has a mp3 hookup STANDARD! :)
I wish I had gotten power doors and windows, but my own fault for not getting them. However, a tachometer would be nice standard on all manuals - not sure why this is considered an 'upgrade'.