My own 2cents is that I would give Tom the benefit of the doubt. GCM began distancing their theology (not necessarily their practice) from GCC under Jeff Kern. GCC and GCM have a "relationship", but my understanding is that they really don't care for one another. There will be the token GCM person who speaks at a GCC conference and vice versa, but they are moving in two separate ways. GCC keeps the relationship with GCM so that they have a vehicle to raise up local missionaries. Other than that, they aren't really on mission with each other. They are kind of like distant cousins who show up on occasion to the same wedding, but really don't care for each other or interact and try to stay as civil as possible.
That being said, I think that the same problems which plague GCC can occur in GCM, but my own experience would be that it is not to the same degree as it is in GCC. I could point out what I believe are flaws in GCM "churches", but it would be more of doctrinal flaws than abusive practices, like I have witnessed in GCC.
My experience and observations agree with MarthaH's, and it's really refreshing to see such a viewpoint here these days. Thank you, MarthaH.