Canola is controversial in the UK. Last time I heard, most canola grown in Canada was GM, enabling farmers to use glyphosate weedkiller on the growing crop. Well we don't allow GM crops here. Oilseed rape is lovely and yellow but it is environmentally unfriendly, requiring lots of pesticide input, and it requires heavy nitrogen fertilising. I haven't researched the other oils as much in these regards, but I won't be buying canola/rapeseed oil any time soon.