I have been dealing with CMP since they converted from the DCM, and the DCM long before that.
The CMP does not sell junk. If they sell it, you can count on it working, if not they will make it right.
Of course, there are exceptions, but they are up front with those exceptions, such as a bunch of tooth brushes they dug out of the stocks of rifles they inspected before being sold. They sold the brushes on their auction site.
They did have a warning, recommending they not be used as tooth brushes.
They sell drill rifles but advertise them as wall hangers not shooters.
You wont go wrong buying from the CMP.