I heard it can completely crash your system if your a noob.
You can crash anything if you try. Been there, done that. Just go ahead and start using it. Just keep backups which you always do, regardless the O/S and situation. (pro tip: TEST RESTORING THE BACKUPS)
Maybe make an extra backup before you try something and you'll live. You could also use a separate partition to store your files so you can re-install without touching your data. Make that partition size 'recognizable' (t.ex. the biggest by far and label it) so you won't mess up the partition selection when you re-install. And NO don't ask me how I know!