Board Thread:Theories and Speculation/@comment-28252336-20160512015637/@comment-734582-20160512084309

Omnibender wrote: Like I said, Madara would not trade his Rinnegan for Tenseigan. Not to mention, he had one Limbo with one eye, but four Limbo clones with two eyes. Clearly, power is multiplicative with a set.

So as was said above, eyes are strongest when the same set is together. This is both true in Obito's interpretation (two people cooperating) and in Madara's interpretation (one person having both eyes). Not to mention, in the OP's scenario, the Tenseigan would be transplanted, whereas being the original owner of an eye easily gives you 10-100 times more power (both in easier mastery of the eye as well as being able to use it to a much greater extent)