The page linked to has the following line:
There are no recommended torque settings for spinners and the exact number of turns will vary from one vehicle to the next.
I have always relied on a couple of knocks with the supplied hammer or a light tweak with the breaker bar I use for removal. They do self tighten in use - to the extent that mine can be tricky to remove as my painted wire wheels “grab” the nuts.
As the text on the MWS site says:
It is very important not to over-tighten as the threads are easily damaged.
