After two years, the automatic radio antenna started making a loud grinding noise while the antenna was retracting/raising, I disconnected it. The noise sounds like a plastic gear stripped out inside the motor housing.
After three years, the trunk started filling with water. It turned out to be a broken clip on the trunk pressure relief valve located in the wheel well. How this broke, I'll never know, but a little RTV sealant and it was good as new. Too bad I had to cut the carpeting out of the trunk to find the leak.
Also in the third year: The rear passenger side electric lock quit working and the door could not be opened because it was stuck in the locked position. I cut into the door panel to try and release it, but no luck. Six months after that, it started working again, but buzzed loudly. I took off the door panel and disconnected the solonoid. The door has to be manually locked and unlocked now.
Again in the third year: The plastic engine coolant reservoir developed several cracks and leaked. The engine almost overheated. Replacement cost $65.00.
In the fourth year: The plastic engine coolant reservoir developed several cracks and leaked AGAIN. Replacement cost $75.00.
In the fifth year: Yep you guessed it, the engine coolant reservoir AGAIN. Replacement cost - we demanded a new one free--and got it. Mazda is aware of this issue yet continues to sell these things.
Somewhere between the 2nd and third year, the dash lights quit working.
Just this year (#6), the engine developed a rough idle at about 55k miles.