I am afraid I have used it a bit, it doesn't actually save me much time though.
I sometimes use it when I am sending an email to explain a problem or situation that is the result of a combination of complicated reasons, along with suggestions for potential solutions with pros and cons of each. My job is such that I send these sorts of emails sometimes to senior staff for a decision
I always write them myself first but I really am a terrible writer, often my writing is too long winded and I can sometimes feel myself losing the will to live when reading the draft I'vewritten, despite it usually being accurate.
I sometimes use AI to redraft what I have written to make it flow better and be clearer in fewer words, along with prompts about what I am trying to achieve from the communication and from whom.It always produces something much easier to read, and clearer, though the tone is often a little too corporate for me. I live with that as it has improved what I wrote in terms of clarity
To be fair DH who is a lawyer who reads and drafts things scarily quickly has occasionally done the same thing for me almost as quickly and just as well but I have only asked for his help on this sort of thing a couple of times in the past when the potential consequences of being misunderstood were very important it is a bit cheeky to ask him anyway.
I have tried to use it start a draft of something but this has been much less successful. The prompts take too long to get right and it makes mistakes of fact , so all the fact checking afterwards takes ages
It is also helpful in presentations in presenting a long list of bullet points that you want to convey in a more summarised and visually appealing format, though tou do need to check it is accurately representing the facts as you want to convey them
Anither really helpful area where it does actually save time is with spreadsheet data analysis , with less need to remember or understand complicated formulae