CHALLENGE ACCEPTED!!! printed in sainsmart 95A hardness TPU. As you can see in the picture, It doesn't quite sit level with the magwell due to some interference at the top, but this is just because of my rifle. I plan to do some trimming to get the perfect fit. With TPU the piece fits snug and It isn't slick like other plastics, the TPU keeps my hand from sliding around on the grip. All in all, great model that works really well.
Set it to go and watch it print flawlessly, end of story. took about 8 hours on my machine at 25mm/s with 2mm thick walls.