I have SAN Infusion for a long time. However, I think their formula has changed (not sure) but it no longer says undenatured proteins on the label. Good solid product though.
I have been looking at this True Protein site, that is a sponsor on AM. They look real solid and I am thinking about ordering from them. You can custom mix your shakes or MRP or what have you. I never even knew about them until I was just looking through the sponsor forum.