**What are the "real" advantages to owning a Leica?**
I tread very lightly as I attempt
to answer this often loaded question. I've seen too many people trying to defend why they bought a Leica and it's virtually impossible. Many people are ready to throw out spec sheets: mega-pixels, screen resolution, fps, high ISO, gps, etc... Spec wise, the Leica will lose every battle. Even IQ wise it's too subjective and can't be broken down into numbers, graphs and MTF charts. To quantify an M9 or any other camera for that matter is not an accurate representation of what it's like to shoot that particular camera. Each camera has it's unique attributes.
OK, the "real" advantages for me are the way I interact with the camera while shooting. I like the feel of the camera in my hands, I like the highly precise movement of the dials and the reassuring click of the shutter release. I like having a full frame camera in a small body. I like the size of the lenses compared to traditional SLR lenses. I like being responsible for the focus, ISO, shutter speed and aperture. I like the way the world looks through the huge viewfinder. I like the fact that there's never any black-out time when you release the shutter. In a superficial sense, I like the look of the camera. (
Yes, I know that is a terrible thing to say, but I want to enjoy the look of my gear.) The difficulty in explaining all of this is that someone can come back and say this is why they hate the camera, it's all so subjective
The best way for me to answer this would be to hand over my M9 kit to you for a month and check back with you at the end and ask your opinion. There is nothing I could write in a forum response that will convince or explain why people choose to shoot Leica. Many people, family, friends, colleagues ask why and sometimes it's just easier to say, "I've always wanted a Leica." I didn't want to say that here, because I wanted to try and give an honest and genuine attempt at answering the question.
About the X1 vs the X100, it's hard to say. I haven't handled the X100 and it was not an option for me when I bought the X1.