I read Webster's 9th Collegiate Dictionary when I was about 10 years old, cover to cover, and no one would use "quitted" unless they were trying to write someone who was speaking oddly even in the 16th century. Here's a modern and archaic use of the word "quit".
James was tired of being denied promotions or raises while newly-hired people were being paid more than he was, so he quit his job right as crunch time came.
Julia sought the peace which naught but solitude could could provide, and thus she had determined 'twould be best to be quit of the meadery and the buffoons that mocked her.