There's a full API you can use to access your builds and download them - our programs come with an 'update manager' that I developed that checks UCB and if there's a new build it will download and install it.The builds are saved indefinitely (for paid users at least, not sure if there's a free tier anymore and if it keeps builds forever), so if you ever need to rollback to a previous build you can easily do that.For WebGL builds you can test the app right through UCB (not perfect but better than having to upload it to your own server first).For Android builds it's nice because you don't have to mess with installing Android packages that are needed (and seem to always give me problems, Unity Hub is suppose to address this at some point I believe though).For iOS builds you don't have to deal with the 'need a Mac' part (and I hate working on Macs/iOS.).The builds are available online so they are easy to distribute.

Overall though, even with the increased time to build, I think it's very much worth it, for the following reasons: iOS can take upwards of an hour whereas locally it could probably be done in 15 minutes - but with a lot more hassle since you need to use a Mac to do the XCode part and all our developers use Windows. Locally we can make Windows builds in a minute or two, so there's a rather large difference there. Our Windows builds take about 10 mins - but our applications are relatively small, mostly 2D/Canvas UI programs (they aren't really even games since we don't make games.).

Unity cloud build sloqw