fwiw there are many good used tires out there, but you have to remember they aren't going to be given away for cheap: and if you're looking for something specific and someone has it, don't mess around; grab them, specially if they are a good deal.
keep in mind there are two reasons why people sell tires;
1: they are sick of mud terrains and go back to a different brand OR they upgrade from AT to MT, OR a bigger size; essentially this is a personal choice: example, i have jumped from Iroks to MTs etc nothing wrong with the old tires; just bored of them.
2: old owners 'bought new ones' in a similar size tread pattern. but why? well look at them; uneven treadwear, different % left on tires, damage etc. these you can get cheap if thats what you want. but if all 4 tires aren't identical, i'd run. example; the tires i had on my old Grand, i could have sold on kijiji, but i have morals, and gave them away for a bottle of rum, with the promise they would be used only for the rims. why? because i knew they were junk.
my .02 on Canadian tire brands; don't bother. if you want to order BFGs through then fine, but as ANYONE who runs a Canadian Tire brand 'roughrider' (like pook, and me unfortunately) and they can't wait to get these POS off their jeeps. i've NOTHING good to say about canadian tire brands. i'm sure the territory's will be fine for a few years; just hope you wear them out before they fall apart.