Inhales work similar to grabs. Not so sure if Kirby's Inhale does the same thing, given the short range of his inhale.
Anyways, to elaborate on the properties. Ever noticed that if you time a grab just as you're getting hit, you'll only take the damage, but successfully grab? Inhale has similar properties with a wider range, since the attacks actually stop when the enemy is just in front of Dedede's mouth (to ball up and be eaten).
Also, the wind effect with Dedede is much stronger than Kirby's, activating just about where the wind animation starts. However, using it at this long range is a bad idea. Consider short hop Inhaling towards your opponent. That way, they are balled up and eaten almost immediately.
If your opponent is not keen on escaping Inhale quickly after spitting them out, or if they just keep coming back at you, chain Inhale can wrack up some %s on your enemy.