Personal Opinion
I personally think its a waste of time and money.
What they charge for their course is not cheap and if you really think about it, there is not much as to what CX is looking for in a cadet pilot. In the interview they are looking for knowledge and passion. If you need to train for answers to prove these things - dont you think there it something wrong. Preparation is good, absolutely, however training applicants to be photocopies of each other can only be detrimental for the cadets. CX HR will smell you miles away.
Anyway.. these are my thoughts .. primarily because I believe I can do it without this Flightexperience.com stuff, and secondary reasons actually are that I want to know what they are teaching the 35K paying kids down there and thirdly because I cant bloody afford it !