Same here, Dave. I wasn't a big fan of the 1907, but since I have a couple of 'brooms' and Lugers in my safe, I figured that I need one. You know how things like that multiply, now there are 2.
The ammunition is another interesting line of study. The Borchardtt cartridge [headspacing on the shoulder] was the 'parent', refined in the Mauser, and shortened in the Luger. The best story is for Luger to maintain the grip size but another good one is that Georg didn't want to share ammo with the Mauser. When the military wanted a larger bullet for the Luger, the 9mm Parabellum was born and we began headspacing semi pistol cases on the case mouth. And along came John Moses Browning...
Yes, the development is simply incredible, especially happening so soon after 'smokeless powder' came into reality.