I’ve had clients ask about using a teleprompter and my response is a based on the event, the speaker, and the audience. Using a prompter sets a tone of formality and it can be misinterpreted as a sign of pretentiousness in the wrong setting. And if a speaker has an informal approach in most circumstances, I would stick with what works with their personality. That said, it’s not a bad idea to know how to use a teleprompter, especially if you plan on doing a lot of public speaking. You never when you might be asked to address a stadium full of people!