The only difference I've found between Uplay, Steam and Origin is when it comes to reinstalling.
I've got all my games installed on HDDs, so when I install a fresh version of Windows on an SSD, I simply install the client (Steam, etc) and point it towards the drive with the games installed. Steam recognises the games are all there, shows them as installed, and then installs pre-requisites the first time that game is launched. Origin says no games are installed, but when you go to download one it then recognises the files are then and sets it up for use. Uplay doesn't recognise anything's there at all. Tell it to download a game and it'll happily empty the game from the folder and dumbly download the whole thing again from scratch.
Might have changed since I installed Windows 10 at launch (my last Windows change) but I doubt it.
Once installed and set up, my only issue with Uplay is that I open it so infrequently to access the 5 games I have on it that it always seem to need an update installing when I do finally open it.