There is lots of info out there on the net that can give you a real good idea on how the interview will go. You may have already seen them. I didn't spend money on formal interview prep and after I interviewed, I was glad I didn't. Some would say it is a small price to pay and piece of mind for a multimillion dollar career, but I was comfortable doing it without it. The interview was probably the most laidback interview I have ever had. Be yourself, be personable, answer the questions with the "STAR" method and your golden. If you get the video interview and then subsequently get invited to Dallas, they've already hired you and it is yours to lose. I wouldn't waste your $600-700, but that is just my advice. This is not Delta. These interview consulting outfits are making a killing and for some guys apprehensive about interviewing, it may be worth it, but I'm here to tell you it probably isn't necessary for AA.