So....I had ECT on and off "acute (3x/week) to maintenance (1x/2wks) for about 4 years, just ended in June 2013. At first, and for a while, the ECT really did help me to feel better. I even kept working P/T while I was in tx. I had no real memory problems for quite a while, then noticed I had no "internal map" of this city that I lived in for over 25 years, and did not remember places where I used to live. I started to lose other long term memories, including my son's childhood, major vacation trips, etc, about a year and a half ago. My depression relapsed so deeply I was inpatient more than out (6x admitted over the course of Mar-July 2013), and in fact, while I wanted to continue w/ECT, my ECT pdoc decided to stop and refused to treat me: due to the memory/cognitive effects and b/c it was not helping anymore.
I would say the same thing about ECT as any other tx for mental health problems: the tx that works depends on the individual and their unique response to it.
In terms of considering ECT or not, definitely check out the latest research studies before agreeing to it. Know that you don't know how it will affect you until you try it. Know also that there are many other, "non-traditional" paths to wellness as well as the more popular medical ones.
Good luck to everyone...feel better soon!