It's working out very well for me. I started training with the four pillars in late april, and have since taken 10-12 lessons with Robert over skype (at least I think so, I stopped counting). My only experience as a singer was school choir and backing vocals in bands, so Robert has pretty much trained me from scratch.
The workouts are pretty tough, but I'm gradually getting better and have started to like my voice more and more. The most noticable thing is that I seem to have added 4 or 5 notes into my 'comfort zone', and the tonal quality and resonance has improved. The four pillars program is very thorough and informative, but I think the lessons I take are an equally essential part of the training. There are several reasons why.. 1 - you avoid wasting time or injuring yourself by performing exercises incorrectly, 2- sometimes you need to be told the same thing 100 times before you get it (at least in my case), 3- I find the lessons keep me motivated.
I'm enjoying training with Robert so much that I'm flying to Germany for one of his masterclasses.