Time wise - same as ducks. You need to feed them, water them and clean out their coop.
Ducks don't always put themselves to bed - you can get them in the habit of doing so, but some nights, they just don't wanna.
I have both. I find the chickens just a bit easier as there is no swimming water to deal with.
As for clean up - I think the ducks clean up easier as I hose out huts and their poop is much more watery than chicken poop. Same goes with the yard... I find myself scooping chicken poop when I go out and clean up after the dogs, but I've not yet scooped a duck poop LOL
My chickens are content to hang out at my feet. My ducks would rather stay at least an arm reach away.
They each have their own types of personalities.