I am a first time duck owner of only a few months, I also have chickens and they all get along.
I will give you my opinion.
I adore my ducks. They are however, a lot of work in some ways, I change their pool water about every 1 and a half to 2 days, as it gets stinky and they love to put whatever they dig up in the mud, into the pool to wash it off before eating it. so there is a lot of mud at the bottom.
If there is food around, there must be water around, ducks, unlike chickens need water to wash down whatever they are eating, they need to stick most of their bills into it.
Ducks again, unlike chickens take a bit longer to warm up to you than a chicken does, they take their time to trust and are always on the lookout for any sort of danger and to them that might be you.
They can be nervous and skiddish depending on the breed, there is a list out there that will tell you the temperament of each breeds and such.
Some breeds can be loud and some quiet, so that would be something you would want to look into.
Some fly some don't (I made sure I chose breeds that wouldn't fly) I have an Indian Runner, Rouen and 2 Swedish.
I would recommend having your ducks sexed before you get them, because I am pretty sure I ended up with 2 drakes and 2 ladies. and that isn't good. and I might have to get rid of one of my drakes which is heartbreaking.
Ducks are pretty much easy going little guys/gals and are very amusing to watch.
If you are looking for a duck that you want to be able to hold and be a part of your family, it takes patience If you are just looking for eggs and a duck to help with your gardening (bugs and pests) then Indian runners are great for that.
Indian runner ducks are known as a skiddish breed but my Gabby is actually one of the less skiddish now, she will eat out of my hand and come up to me to nibble on me, but I spend a lllloooot of time with them.
A Rouen is also a wonderful breed, Zeke my drake was the very first to start warming up to me, and what he does everyone else does. lol.
A duck is a wonderful thing. They are easy to take care of, they just require the proper diet, lots of cleaning up, patience and love.
And if you decide to get some ducks this is the perfect place to come for advice!
Good luck to you
I change it every other day unless I am walking by and one is standing staring at the dirty water and side eyeing me - "You're not going to leave this like that are you?" 
