I failed my PMP on my first attempt this July, and really want to be sure I pass it on the 2nd try in late November.

I am doing self-study, and taking practice tests, and have found advice on this forum very useful, but think I would also benefit from an online PMP course (cannot do a classroom one due to my work schedule).   Any recommendations about the best ones out there?  I see some sites offer a guaranteed pass--is this worth the extra $$ to get this guarantee?