The American Amazon is ten times better (and cheaper in some cases) than the Canadian one, but they won't ship the majority of the stuff outside of the US
Amazon I use mostly when I have Prime membership or if items on there are cheaper than they are elsewhere. I also use eBay a lot for buying CDs and stuff so it's kinda equal I guess.
I like Amazon better but they just increased the price of the Prime service by 20 bucks! I feel like they need more competition so that they won't get away with constant price increases!