Granted. Eventually, everyone and everything you ever knew and loved is gone, and centuries pass like seconds because there's just so much time crowding around in your brain, leaving you hopelessly farther and farther behind the learning curve of new technologies. Also, when the planet is consumed by the sun, you survive, drifting in space alone, forever.
I wish for the ability to make perfect clones of people, including their memories, just so I can settle once and for all the debate over whether Hitler was religious.