I've been considering using CDs such as these for a few years now. My main objection is that I don't want somebody else's 'buggy code' inside my mind. From a coding perspective, you could view my personal model of PD as being similar to
LFS, where basicly I write my own 'Distribution' or 'Development Plan' with only the 'code' that I have personally signed off on. I might feel differently if they were 'open source', where I could 'open the hood' and see what was going on and what they were trying to do. I can do that with books, blogs and lectures, but I'm not sure how that can be done with Paraliminals. As it is, if these CDs don't work for me, I would be more concerned with 'uninstalling' them than I would be about any warranty offered by the vendor.