I just got mine and it is phenomenal......The 45c is a great gun and for CCW perfect. But at the range it is great to pop in that mag with the x grip and go to town. I use it for some matches and the advantage of 11 rounds over 9 to start can add some precious seconds......Highly suggest it. Got mine at Greg Cote, LLC also.
I have the same X-Grips for my 40c and they work and feel great, great for going to the range, not necessarily for carry though if you are my size 5'6" and 140 -145 ponds!