So basically your own personal Groundhog Day or essentially freedom to live your whole life with a twist? I guess I'd choose never sleep; there are species in the world that don't actually require rest, so it's entirely possible theoretically to adapt to the sensation and reach a point where you can function normally. Sleep is nice and all, but in the grand scheme of things, it takes up a lot of ones already short life.
Would you rather:
You know the solution to every problem, but can't apply the solutions.
You have the means to solve any problem, but can only solve 1.