I was always a healthy weight but after having a baby at 35 I just couldn't get my flat stomach back, so at 40 decided to undergo TT.
Now three months later I'm having no regrets, although the recovery has been a long road. I don't know if there's a proper medical term to describe it, but essentially a portion of the flap (about an inch in diameter) right above the incision failed to close completely. My doctor removed all the tissue, going about a half-inch deep below the skin surface, in order to promote tissue growth and healing. So basically up until now I've been walking around with an open wound but it is finally closed up and it doesn't appear so far that there will be any permanent scarring. I was told that my results are extremely rare (wouldn't you know it had to be me) and while more aggressive action could have been taken to deal with it my doctor encouraged me to give it time to see what my body could do on its own. That turned out to be the best advice - looking back on it, of course it was not fun to deal with it for 3 months but I'm very happy with the end result.
I wouldn't discourage anyone from having a TT done although I would recommend having expectations that are as realistic as possible. A good doctor will give you that dose of reality and prepare you for the possibility of a slow and/or difficult recovery.