I have attended CIC and MIC courses and have listened to most all of the early seminars as well as phone conference calls and early OM. GTEN and Order of Merchants kinda seemed to spawned out of CIC. Christian, PJ and Zach knew Brandon and attended early classes, but I doubt they got all their information from CIC, as they all seemed pretty knowledgeable from the start. PJ was in my group in MIC and was way more knowledgeable than most especially in what interested me... Trusts.
I thought MIC was great but it seemed to run out of steam once people left the meetings. It emphasized networking but it slowly disintegrated from lack of participation. That was MIC 1 and I have not really been following as of late so it may be different now that more people are participating and the bugs worked out. MIC didn't really get as in depth about trusts as I would have liked. Luckily GTEN started to offer more discussions on the topic. I was sold immediately.
The info provided by CIC, MIC, OM, Gordon, etc. and GTEN all play a part in the development of our understanding of who we are, what we are capable of and how we can operate in this reality efficiently. They all have great info. Study it all and choose what works for you.