The retention is about the same as received from CRK. That said, I gave the MIM clip a slight bend for tighter retention and the retention ended up being perfect for me and is holding the adjustment well. For me it's an improvement over the stock clip.
Just to give some context... I'm usually in jeans or my work pants. The leg cargo pocket of my work pants or my jeans pocket are perfect thickness for the stock clip, but the side pocket of my work pants, which I sometimes carry my knife in, is thinner. I like the MIM clip because, with a slight adjustment, it is secure in both the thinner and thicker pockets. I couldn't get the stock clip to work well for both.