I agree with TheHealer. It would be most beneficial to combine forces, teach each other all that you know and teach those of lesser knowledge together. Two satanic covens, to me, seem kind of pointless, but combining your knowledge would benefit both of you as well as those who join your coven.
Since we can only be in one coven someone could join Neckron's and perhaps never know that your's, satanshost, would be better suited to that someone. Likewise someone could join your's and never know that he/she should be in Neckron's.