Mammillaria insularis - two side by side showing differences in flower

I posted this originally as boolii and insularis, but thanks to a member who has looked closely, I now think the plant on the left is M. insularis as well, even though I bought it as a young seedling of M. boolii.

But the spines are not right, and this is one of the defining characteristics. So I must relabel!!

And find a proper M. boolii!

I've got some spare ones Chris.