I am also considering the NET scheme and yes, it's very difficult to get any information on it! Having spoken to a few teachers who know teacher's that have done it, I can tell you that your experience with the NET scheme really depends on the school, and of course your own attitude.
It's probably a good idea to be in HK and attend several interviews (at schools) before you decide on which one to go for, and if you actually want to do it! HK schools are quite different to schools in the western world. Not sure if you're here already or overseas?
Also, are you already a teacher and just looking to get a TEFL to allow you to teach ESL, or do you have a completely different background and just looking to switch lanes?