"I want to believe" in overunity.
why?
Because without it and Q-thrusters and EM drives we are stuck to this solar system.
Why, 100 k years to get to the other side of the galaxy isn't that long, haven't you always wanted to watch all videos on youtube during your flight from A to B?
Or read all books ever written?
Some small nuclear reactor, or normal hot fusion reactor is enough to power some live support machines for 100k years,
you just need to work on human longevity and you will not be stuck to this solar system no Mather how slow you travel.
And in contrary to breaking the energy conservation laws there are no known fundamental limitations to human longevity, achieving (a)biological immortality is just a Mather of some more technological progress and once its done subjecting your natural biological body to enough treatments and augmentations.
Edit: and of cause before all living long enough to be still alive when this technology's will become available.
Trax