+ access to folders on a iMac/MacBook desk from your iPhone or iPad
+ if you have more than one Mac you can remote access the other desk
- can eat pretty much iCloud storage. (I would say at least 50GB is recommended). If you have tons of folders you need 200GB or more.
- the Files app is not the most comfortable to use if you have many folders and subfolders.
- some Containers (for example dmg or sparse.image) can not be opened from your iOS device.
In my opinion it makes more sense if you are using to different Macs. On iOS devices it is more kind of a "emergency remote access tool" (for example if you need a pdf file on you iPhone while you're on the train.
I have it enabled but I don't store many files on my desk and I have only 50GB of iCloud storage (about 50% used).
I have a work computer and two personal computers (one laptop and one stationary). Having sync is amazing. I can access all my documents from all computers.
My only gripe is that there are no finer control of it. I would like to define namespaces, for instance "work" namespace should have access to folders X, Y and Z whereas namespace "home" should have access to everything the work namespace has access to, but also folders X2, Y2 and Z2.
I would also like to sync more folders, like Downloads and even the contents of the home folder but I guess that will come later.
All in all, definitely worth it! But has the potential to become much better as well.