The small form factor is great.  This is a nice, powerful machine for normal home usage - I did not buy it for gaming.  What I wish I'd known before buying this particular model (Mac Mini M1 Chip with 8GB RAM, 256GB SSD) is that macOS does not let you choose where to put some data that I had expected to be able to put on an external Thunderbolt drive.  I don't count that OS issue against this particular machine.Do you use OneDrive?  While it let me say I wanted OneDrive on the external drive, it sort of ignored that and put it in the hidden library on the tiny internal system drive.  I didn't need my OneDrive stuff there.Do you use iCloud Drive?  You do not even get to pretend to say where you want that data to live.  Of course you would not have more in your iCloud Drive than will fit on this machine.  For iOS, you can say not to automatically copy all the iCloud Drive data.  MacOS doesn't give you that option.  It does have an "Optimize Mac Storage" option, but that will basically fill your drive with as much as it can, leaving your drive pretty much full all the time.  Later, if you need lots of space for something big, you may not have enough room to get through your task.Had I known this beforehand, I would have opted for a higher capacity Mac Mini.  I didn't want to use my high performance storage as the local cache storage for iCloud or OneDrive.You can move your iTunes library to an external drive if you want, and I believe it is somewhat normal to expect to be able to offload things to the cloud if you have more than you can store locally, so it was an unpleasant surprise to find that you can with iOS and iPadOS, but not so much with macOS.