I've had 2 problems with my 330 - transmission software and recalled coils. Both were handled well by BMW. I am extremely satisfied with the cars despite these 2 problems I personally consider minor.
Others would certainly consider these items a crisis - it's all about your perspective, which is really my point here. I'm not really trying to influence your decision so much as paint a perspective to consider and research.
1. Whether you but a BMW, Toyota, or Kia, throw away that Consumer Reports auto buyers guide. It's flawed in so many ways it's insane, yet people consider it the bible in new car buying.
2. Read the JD Powers Initial quality reviews and customer satisfaction reviews. They know A LOT more about car studies than an organization that makes money from selling magazines and puts reviews of hair dryers next to car reviews. For example, read this article and the following excerpt:
http://autos.msn.com/advice/article.aspx?contentid=4020143
This year there were a number of vehicles and brands that scored highly with very few defects, yet they were penalized for what could be considered design flaws.
"Without considering both quality factors, one might fail to recognize vehicles that are, in fact, excellent in certain ways," said Ivers. "For example, BMW vehicles have among the fewest defects and malfunctions, along with Toyota. But BMW approaches controls and displays in a way that creates some problems for customers, leading to more design-related problems overall than Toyota incurs."
3. Consider why the negative owner reviews were posted - because they had an issue. How many happy satisfied customers posted a review saying they were happy? Unless they are a car enthusiast like some of us nuts here, happy car owners don't make noise about it.