Sure. So I don't get the point -- either the material will be some sort of 304 rubbish or worse (easy and cheapo to manufacture) or something decent. If it's rubbish it'll start rusting and etc. as soon as it sees some salt and cat heat, regardless of whether it's welded or not.
Generally rust on SS exhausts is due to "specialist exhaust manufacturers" using mild steel wire to join otherwise adequate grades of stainless together. They should be lynched.