Yes I do.Seems to work here using Firefox 6 - By quick edit do you mean the popup / overlay box?
I'm using FireFox 7, and have just tried editing a post 10 times, and each time it worked as expected. I don't know what you mean about getting an edit cursor in the window? I just click anywhere in the text box, and the cursor appears. Does this not happen for you?I use IE8 and I see the same kind of pattern - I hadn't twigged that it was alternating though.
For anyone who has not seen it, when you click "edit" under a post a pop-up appears with the post text in it - but then it's pot luck whether you can get an edit cursor in the window. If not, by clicking "more options" the pop-up is replaced with a full browser page edit screen - and the cursor etc works properly in that.