Yeah that is a great doc, I own a full copy of it. I was surprised the first time I saw it because I thought the stocky blond FTM at the beginning was a genuine boy.
If you liked that though there was also that show Transgeneration that Sundance put out. SoCo was better imo, but Trasgen still has a lot of good moments and stories (well Gabrielle is a bit of a headache).