Oh... didn't notice the efficiencies listed, thanks.
Provided that anti-matter is stored in the form of anti-hydrogen
and with advanced superconducting containment technology, I believe
that future containment problems could be solved and draw relatively little
power. Production efficiency is doubtedly an issue, if anti-matter
is used it is likely to be produced on Earth and trasnported to
the spacecraft that will exploit its energy.
Don't wan'na go into politics.
Live long and prosper.