I can see room for improvement about the UI, but I like that it works everywhere and I use it to, obviously fix grammar and mistakes, to add/change our company's specific vernacular (finance), and to change common LLM sentence forms so that the readers don't notice that content was made by AI. Ya know, all these em dashes, "testaments to", "this isn't just X, it's Y", etc.

My favorite function of the UI is that, on any website, pressing TAB just fixes/improves what I just wrote before.