I've had it twice, and am stunned by its power and effectiveness in removing the negative charge attached to memories from one's youth and later. RET simulates REM sleep, but while you're awake, and over the course of 90 minutes per session, in the skilled hands of an experienced practitioner, can draw out of your stuff that you didn't even know was there. As I said, I've had it twice so far (as part of a course of six), and each time I only feel brighter, better, lighter, and substantially relieved of past hurts.
My partner's had it to and some of my friends. Only control freaks, those who have a problem letting go, seem not to get any benefit from it. The rest of it were moved, and we experienced profound psychological and emotional changes. I'm a total fan of RET.