I'm guessing you are going to get some very different responses to this.
For me, I am happier. When things are good, they are really good, because people treat me as who I am. I've loved the body changes I've had, I feel better about looking in the mirror, and people seem to like me more as a woman than they ever did when I was trying to be male. This is probably because I'm easier going and more genuine now.
But... I still get dysphoria. There's a lot still to battle through, especially negative body image and fears about relationships. I'm going to be having SRS in 6 months and that is scary but at the same time can't come soon enough. But it's still a major surgery, and it's going to be tough.
The absolute crux of the matter though is this (and this is what I try to keep in mind whenever I get depressed): If I hadn't been able to transition, I'd be dead. This existance may not be perfect, I may still wish I'd been born female, but it's the only way I could have continued.
Whether you will be happier or not will range on a whole load of different things, such as how happy you are with your appearance, family/friend's reaction, job security, personal outlook etc. I'm prone to anxiety and depression; I come from a family of people prone to anxiety and depression. Transitioning will not solve all of your problems and worries. It may put you in a place where you can better tackle all of those other issues though. Dysphoria for me was like a raging layer of fear and self loathing that covered everything that I did. It drove me down, transitioning has risen me back up.
