validating the integrity of the installation
The ISO file should be validated, and many installation medias check hashes.
it can be disastrous if you don’t pay attention to what you type in
Valid point, even I get nervous when entering dd.
I don’t think that dd alone should be used as a backup
Absolutely it shouldn’t. I said primitive backups, which are not a replacement for things like snapshots. DD backups are space-inefficient, easily corruptible, and often result in broken systems.
I bought two of these a few years ago and they are really reliable. USB 2.0 so they are slow as shit, but I still use them to install linux.