Not a perfect fit on some receivers i guess.. - Magpul Industries MOE K2 Gun Grip

I love Magpul and the quality of their products. This one looks great and feels great. I like the angle of the grip. I like the width. The cap on the bottom is extremely tight-fitting, so I doubt it will ever accidentally pop open. However, it does not fit perfectly on my new Aero Precision M4E1 lower receiver. I thought at first it would not slide on at all, but with some firm pushing, it did go on. The back part of the grip where both its contour and the contour of the receiver curve upwards to meet the buffer tube, there is some space. Not a ton, but enough to notice. I am leaving the grip on, because I otherwise love it. It also is just a tiny bit different in color than their FDC Cerakote that I have on the receivers and handgaurd...