Hey Yo,
Better late than ever on a response I guess. I don’t think there is any deterrent to any one method being used. Anytime spent in meditation is beneficial. I had used Holosync as well and agree at one point it was necessary during my own personal growth. I am not trying to put it down in anyway but feel that in my own experience it would bring me to a point and that was it. In someway it brings you to a point and holds you there and can be a distraction to your potential progress. In away it was like using training wheels and at some point you have to move on from it. If it is needed in the beginning then so be it but don’t rely on it.
Shr33m mentioned a great analogy to consider and that was if you were on a desert island with no power, walkman, CD player ect, how would you manage. If you are going to spend your invaluable time investing in meditation then why not focus on the gold, the end result is well worth it in the long run. The benefits are that you have no reliance on outside means, better discipline of the mind, your surrounding become part of the experience and so on.
As Shawn stated everything you need is in lvl 1. By following the program you build a foundation, a natural ability to reach the alpha, beta, theta states of the mind. You also open up the door way for going beyond where Holosync can keep you. Sure in the beginning you may have to contend with the babbler more often than desired but this diminishes with time. The best thing is that it diminishes naturally as you focus on self healing by focusing on opening your energy channels. This Holosync can not do for you it will only bring you to a state,,, then what. Why not put the focus and intention where it would do you the most benefit. So I guess ultimately the determent would be to your own path and potential growth.