hmm, shouldn't have a significant effect on taste, if any.

The scion determines the fruit; the root only the speed at which it grows and tolerance/resistance to various organisms.

Chandler pomelo stem grafted onto an Oroblanco grapefruit.

They both share a same parent, Siamese Sweet, so should be extremely compatible. graft was made a little over a month ago

in some cases the rootstock can actually affect the flavor a little bit, but mostly not.