I was under contract for 7.2 cents a month and elected to let my contract go to variable rate, which per their website says you can save 3% guaranteed (I have screen shots and downloads of this to prove it.). However, my rate jumped to 15.9 cents and hasn't gone down since. When calling to complain about this, I got the line from them that they because I failed to renew my contract that they switched me the variable system, which by everything on their website should be cheap - I have included screenshots and their own documentation. In fact, non of the competitive rates go that high on their website. I've filed complaints with the Utilities Commission and the Attorney General in PA.
If you Google Ambit energy and class action lawsuit, you will see I am not alone in this as.