The specs sheets can be found on the product page of Canadian tire's website, under additional info... it will send you to a PDF link
All the specs sheet say right on the first page that the manufacturer/suppler is Shell Canada products
So yes, motomaster oil is seems to be rebranded shell
However, for example, it is a different formulation from the Pennzoil/quaker euro 5w40, according to the spec sheets
I have 2 Hondas and 2 VWs in the family and I plan to use motomaster from now on, it's the cheapest by far and meets all the required specs as far as I'm concerned... I have the 5w20 in one of the hondas (01 accord) and it runs fine, but obviously this is ancedotal evidence of my butt dyno... to get real results would of course entail and oil analysis,which would probably be overkill... it's a honda it'll run on vegetable oil