I personally do not dig sleeping with my cats. Mostly because they would just mess with my stuff all night long and either wake me up or eat my stuff or likely both.
However, people who do sleep with their cats, or at least with their doors open, might find that cats have an obnoxiously early internal alarm system and will inflict this alarm on you. You might be woken up by them running around like a crazy person or maybe kneading your chest or face with their cute little beans. And no matter how many times they do this to you, you will keep loving them and leaving your door open. Crazy how love works, isn’t it?