I guess I overstated the "horror" stories. I've just read that lots of people have had great difficulty in regulating the thyroid replacement hormone and have had other effects--huge weight gain, arrythmia issues.

Bx was not fun, only local anesthetic. All three docs, as well as the endocrinologist told me that a thyroid biopsy doesn't always give the answer--I don't even know why they do them. At any rate, it's not an emergency, so I'll take some time (and another opinion) to try to figure out the right thing to do.