I opted in around eight weeks post-op. If the next question is about the difference it made, your guess is as good as mine. So many variable play a part in recovery/repair. My thinking is, if the money is available, history of cancer low, and even a chance it will help, why not.
Yo, Maz....if you read the novella of my experience via my shitloads of posts in here, you'll see that I pretty much noticed nothing until day 108 or so.