Funny thing about people's opinions about cars. Everybody has one. You're correct. Head gasket failure is mentioned regarding the Subaru 4 cylinder engines. However, based on my personal experience, and that of my family and friends, none of us have actually experienced this, nor any other major issue with these vehicles. One of my son's lives in Massachuesttes, in an area that can have snow from early October through the end of April. Around there, a lot of people who prefer a car-like vehicle, drive a Subaru or an Audi.
As I research the purchase of a new vehicle myself, for whatever vehicle I investigate, I've found that the Internet is full of poor quality claims (oil comsumption, brake wear, transmission, electrical, suspension, etc issues). At the end of the day, at least for me, after I've done my research on the Internet, while helpful, I look to family and friends to see what their experience has actually been. Also, particularly for a vehicle purchase, I take a very serious look at the dealer's business practices and the capability of their repair shop (all vehicles, at some point, will have a problem). Once the vehicle is purchase, it's been my experience that the quality of the relationship you have with the dealer is of utmost importance, particularly is a problem is encountered that requires their assistance in working with the manufacturer.
PS: My neighbor traded in her BMW 3 series for a Mazda 3. She loves the reliability and gas mileage, and lower cost of ownership, but misses the power and sportyness. Every decision has tradeoffs.