I used XMonad for many years and finally had to give up and switch to i3, so I would recommend using that
The first problem was that they broke my configuration file with every release. I'm not a Haskell expert so fixing it was very time consuming
The second is that their gnome integration is quite bad. Also it's different for every combination of XMonad version and Ubuntu version and eventually I hit a combination that I couldn't get to work
So it was great when it worked but it didn't always work, and I'm now a happy i3 user