I am not aware of any rotors being made in Canada, everything ships over from China pre-machined and coated. That's not to say it's no good quality, the Chinese foundries are capable of excellent quality, assuming the importer/distributor has spec'd it that way. Actually I am not aware of anyone manufacturing rotors in the US either, it's largely China with a couple European exceptions.
Pads are similar, though the process is a little more small-business friendly, so there are some independents producing in North America, including one guy in the GTA. There also seems to be a bit more variety in country of origin; India, Taiwan, etc are players in pads.
The biggest variable when it comes to regular daily driver style rotors is the longevity of the coating...Which is a function of not only the coating itself, but the metallurgy of the rotor, a higher quality metallurgy will be less susceptible to rust, and thus the coating will stay on it longer.
I haven't used Max Brakes....But I might try some just to see what's up. I did put a set of MotoMaster rotors from CT on the DTS when I got it around October 2018 and to date the black coating on them has held up very well. Sample size of 1 though, and I don't have anything to directly compare it to.