If you remove the “feel” and the experience of shooting manual with this tiny body and tiny lenses than looking at the images alone, you would be hard to justify on a business level to get a Leica. Certainly won’t be finding them shooting at the Olympics or for Nat Geo at the South Pole for Empire Penguins.
My observations is that most Leica users buy it for the lust for that brand, out of their own pocket, it is a bit like wanting a Gibson Custom Shop. Why would you spend £5,000 on a guitar when a £500 can do the same thing and to any listener, it would sound 99% identical when you play a song, most of the feel would be down to the player and the music. And that 1% in feel, that £4500 extra is purely to satisfy the player who is using the instrument, which I am sure is important because as a user, you want to feel good playing it, I too am guilty being an owner of a Gibson Custom Shop so I understand that side of the argument but I am not a professional guitar player so for me, the importance of feel is more like than 1%. It’s like expecting having a quality guitar to make up for my lack of talent, expecting amazing results just because of the quality instrument but the truth is the money would be better spent on lessons and then get a cheap guitar…(I should really do that but the Gibson is so nice!)
The difference is an expensive guitar does the same job as a cheap one, except an expensive Leica does less than a cheaper Sony or Canon or Nikon camera. You end up paying more for less.
You can, if you want, get best of both worlds by getting a Sony body with a Leica adaptor and put on a Leica glass in front. To be honest, there are plenty of great FANTASTIC glass on other systems, Zeiss makes equally good glass on all kind of mounts, some of the Canon L is up there too like the 35L mk2, Sony GM is also fantastic, so is the Sony Zeiss 50/1.4 and I only heard good things about the Fuji X-mount glass, well I have a few of them too.
That said, I have never seen any Leica user said they regret getting their Leica, perhaps there is something about it, but is it worth the extra? I feel like I am too poor to even ask to try one, one time I was in a Leica dealer store in Hong Kong where I recall they had gold plated limited edition bodies. I had with me at that point a new 5Dmk3 with a 35L over my shoulder, even with that in hand I feel like I didn’t belong there. The aura the brand is such that they are more a luxury brand, like a Prada bag or Tiffany necklace or a Rolex Submariner than any kind of tool to take photographs with.
As for build quality, I am sure the Leica is built well, but I’d be surprised if it is built as well like the 1Dx or D5, where you can take it out in pouring rain for hours and be abused in all kind of scenarios. I might way off the mark with a general statement but my impression is that a large percentage of Leica users tend to baby their camera and put it away when there is a first sign of rain, and then call it “well built”.
It's not like you see a huge amount of pros with Leica, so what gives? Are they just a fashion accessory? For people with more money than sense? 
