I respectfully disagree with your comparison of a Mamiya to a Kia. But since you seem not to like Mamiya, you can instead buy a P65+ to mount on a Contax, Rollei 6008, Mamiya RZ, Mamiya 645, Hasselblad H1/H2, Hasselblad 500 series, and in addition use hasselblad 200 series lenses, pentax lenses, or use any of dozens of view/technical cameras. We've even had customers jurry rig a digital back to a Holga.
So you can have your 1000 horsepower in any flavor you want.
Well, I still think the car analogy makes sense and let's be realistic, these cameras have been compared to cars since day one. Michael mentions Mercedes and Toyotas in his article and in fact most reviewers rarely fail to draw a medium format camera to luxury car comparison. Personally I don't see a Mamiya 645 as a luxury item, but to each his own.
Even the current pricing of medium format mimics cars. Today you can buy a 2 year old Maserati for the price of a new Cadillac, a two year old Cadillac for the price of a new Toyota and looking at the demo prices from all the medium format makers today might be a good time for someone that is jonesing for a medium format back to buy a demo back, a used blad or Contax and start shooting, pretty much at the Toyota price.
What I really fail to understand is everyone talks about the upgrade path of medium format cameras (not backs, cameras) and seems to worry that their blad or contax has no where to go. For some of us, no where to go is a good thing because I doubt if my Contax will need a firmware upgrade and I have yet to travel through a city where Contax 645's weren't for sale. On this forum Hasselblad has a deal to have your H1-2 refurbished at bargain prices, so in my mind these old cameras are sill very viable. I have had 3 brands and 5 models of digital backs mounted on the Contax and each in focus image is razor sharp, so I'm not real sure what any new system will give me that I need. Need vs. want is a different thing.
For digital I looked at the Mamiya, (briefly) but didn't understand the advantage over a Contax other than the dealers were selling them in bundles. The Contax has a fast lens line with the only hole a 100 to 110 f2 prime and regardless of current thought I do use the waist level finder a great deal, as 70% of everything I shoot for commerce is now horizontal and try shooting ground level horizontal with any fixed prism camera and you'll wish you had a chin guard. Even if two or three years from now some company like Mamiya or F+H comes out with something I just can't do without, the costs of the Contax is so low and the used market still so robust that selling it would probably not result in a single lost penny. The digital back won't hold it's value, but the camera and lenses will.
Let's be realistic. From a professional standpoint few of the new cameras are a "must" buy except for a few rare cases or for rental houses whose photographers know little about the digital process and just say "give me the biggest one on the shelf".
For rental guys 60mpx makes sense, for photographers that shoot for commerce and own their own equipment, I have doubts.
This doesn't mean anyone shouldn't buy what they want because it's just fun to have new stuff, but just like cars, buying a Maserati won't make you Lewis Hamilton, buying a 60mpx back won't make you Weston and had Weston's photographs had 20% more detail it would have changed nothing.
But to be clear there is nothing wrong with a Kia, maybe even one with 1,000 hp, but the valet won't park it in the front of Capo and just like cameras, Kia and Hyundai are probably doing better than Jaguar and Land Rover.
Obviously Mamiya is doing better than Contax, Bronica, Pentax, but that doesn't mean that had Hasselblad had kept the H system open or Contax was still in production that Maimiya would have ever been a thought in Phase One's corporate mind.
The only problem I have with the Contax isn't the camera it's that the backs have not kept up with the development of the dslrs. Everytime I look down at that tiny lcd I think about selling the backs, but I doubt if I will ever sell my Contax'.
Still, when you start talking about Luxury items, or who needs/wants/can afford something in the world of modern cameras the AFI (god I wish they called it A Rolleiflex) followed by the Blad would be 1 and 2 in bling factor.
I live and die for the photograph, but don't think bling doesn't matter because if it didn't we would all be wearing hemp and walking to work.