mazda6 are good cars, just understeer a bit. mazda's interior is on par with luxury/german cars, it's exceptionally well done for average econosedans. That being said, mazda usually focuses on handling/feel rather than power, which is why mazda's power ratings are a bit below par with competition (ie. 200hp for the mazda6 vs. 255hp for altima 3.5se, 240hp for honda accord, etc)
Test one out and see how it feels. otherwise reliability's pretty decent, keep in mind mazda is 40% ford, and the mazda3 is a reskinned 2007 ford focus in the US, which is the current focus in Europe right now. Mazda b-series pickup is the ranger, etc...I don't know if any of the mazda6 shares components with ford counterparts.