Strong enough to disrupt personal identity, if taken in one shot? That's a difficult question to answer, especially since I don't know what experiment to perform to test any hypotheses. On one hand, billions of neurons in my visual cortex undergo massive changes of activation every time my eyes squeeze shut when I sneeze - the raw number of flipped bits is not the key thing in personal identity. But we are already talking about serious changes of information, on the order of going to sleep, dreaming, forgetting your dreams, and waking up the next morning as though it were the next moment.

It sounds as if you believe in a soul (or equivalent) that is "different" for some set of possible changes and "the same" for other possible changes. I would suggest that that whether an entity at time n+1 is the same person as you at time n is not an objective fact of the universe. Humans have evolved so that we consider the mind that wakes up in the body of the mind that went to sleep to be the same person, but this intuitive sense is not an intuitive understanding of an objective reality; one could modify oneself to consider sleep to disrupt identity, and this would not be a "wrong" belief but just a different one.

I think most people are most comfortable retaining their evolution-given intuitions where they are strong, but where they are weak I think it is a mistake to try to overgeneralize them; instead one should try to shape them consciously. If you want to try being female for a while, why spoil your fun with hang ups about identity? Just decide that it's still you.