I have more problems with it than any other launcher. Most of the time the it works - but even then it takes some time to connect to the Ubisoft servers. However, you can never be sure that Ubisoft games work when you need them. Sometimes there are crashes and connection problems when starting a game. Sometimes an update breaks the launcher for several days. I also had performance problems & crashes due to the launcher overlay (had to deactivate them in Desktop mode).
It is a hassle. So much that I deleted most Ubisoft games from my wishlist.
I’ve played through the whole game last year and the performance is okay.
There are occasional dips and the framerate is rather low in cloudy levels, but that didn’t take away the fun for me.