Not only do the dealers have no clue how to fix the smoke but they are also going broke and are trying to get every buck they can.Do yourself a favor and get the ptp pill to cure the smoke problem. It worked for me and I was smoking bad for quite a while. I did the 5/40 full synthetic oil thing but the pill is what did the job and took all of 5 mins to install. Takes a few weeks to clean up the intake but now I dont smoke at all.
+1 on dealers going broke and ******* everyone they can. You know dealers get comp from Mazda when they do warranty work right? I bet they were paid by Mazda for your defective "PCV" and labor and still hit you for $100.
Want something done right, do it yourself. I would try the PT part AND change the oil to 5W40 and my only concern in your case after that is Mazda dumping your extended warranty if they find out you did it. Of course, how much has it helped you to this point anyway?
Screw them. I will not be buying any extended warranty for my car.