Would it be very still like being in the EYE of an anything?
They've been thinking of anti-matter bombs since the 1960's.
We can now create anti-matter.
Did you see the 2009 StarTrek movie?
One little blob of anti-matter destroyed a giant, planet-mining starship that was capable of destroying entire planets (not to mention Starfleet's armada).
StarTrek is famous for "eject the warp core" (which results in an anti-matter explosion).
In theory, an anti-matter vs matter reaction could destroy far more than any nuclear bomb.
Thankfully, so far all that seems to happen is the two molecules destroy each other and that's the end of it.