Hi there,
I agree all meds should be approached with caution. Side effect profiles and withdrawal syndromes are often minimized IMHO. That said though I did think that one thing about low dose methadone that was interesting was its use for pain control WITHOUT the risk of opiate hyperalgesia which is a real thing to take into consideration, especially for us hyperalgesic folks.

IF you decide to go with it were they recommending an EKG ahead of time? My neuro wouldn't start even a low dose of nortriptyline without one. Nortriptyline has a little better side effect profile than amitriptyline BTW since it is a metabolite of ami...in case you are having untoward side effects it might be worth a try.
Another alternative for some is tramadol. I did well on it (short of it giving me headaches) and it works on NMDA receptors. It is another one though that if taken regularly for a while should be weaned off of. It is not habit forming but can cause seizures if withdrawn abuptly. Oh, the things to watch out for!