We have one of those in the family. The car is basically nice and it has the V6 package which is quite powerful. Problem is, its had endless electrical system problems and is always in the shop. It also had a fender that wasn't bracketed on properly and defective front brakes. I was surprised because I thought Mazda was supposed to be decent, then I discovered it was largely made in Detroit at a Ford plant and realized why it had such a poor maintenance record.
My rule of thumb now is, if something is made by a unionized workforce I simply avoid it the best I can.
I got the 4 cylinder model. Plenty of power and great mileage. I think the quality has improved over previous generations. There were definitely issues with the 6 in earlier years and that made me hesitant to buy one. But after reading reviews of the current generation, I was more than happy to buy one. So far, I am definitely not disappointed.
I don't think the problem is the workforce itself - it's the fact that the UAW is higher cost and less productive (thanks to inflated negotiated pay levels and productivity-killing work rules). Since this added cost has to be factored into the cost of the car, management makes up for it by taking costs out only way they can, by substituting inferior materials and thereby reducing the specs for engine, transmission, electrical and other parts. Note that Detroit is required by union contracts to source a large chunk of their parts from UAW parts makers. Bottom line - it's not only the original parts that come with the car that are bad, the replacement parts that are used to repair the cars are no better. The whole Detroit system is one that coddles UAW workers at the expense of customers, who have to put up with expensive repair after expensive repair.