In Rate or Acro+, yes. Not in Rattitude, unless full stick is configured to be slow.
The problem is that in is unnatural for quads. You can take it up high and make a video that proves that the flip is slow and smooth, but that doesn't help normal flight because a slow flip looses so much altitude.
I have a fixed wing with Rate mode and am an experienced fixed wing pilot. I can't really tell the difference between Manual and Rate on fixed wing.
There are reversable thrust quads and collective pitch helis that can hover upside down that can do slow flips better than regular quads because they can thrust backwards when upside down.
So generally with quads, stay away from slow flips and stick to medium ("watchable") to fast ("instant") flips.