Feel free to unload your P30+ to me!
The interesting thing about open forums is you have so many different types of photographers. Some shoot locked down on a tripod, some are amateurs, so shoot professionally on deadline.
The interesting thing about all of these tests is they don't really equate to real world work.
I've seen (and must admit have done) iso tests where I set up studio strobes and work 200 to 800 iso comparing noise. The thing is I would never use 800 iso in the real world this way. The same with testing the dynamic range of the capture.
When I need high dynamic range and high iso it's because the conditions aren't perfect. The light is usually a mix of kelvin temperatures, backlit, or window light, the glow from a restaurant, and in those conditions any camera I've used at 800 iso has a lot of stuff happening in shaodws, but then again so did any film I used in those conditions, so I guess it's a wash.
You can't open the internet and click on d3x or H3d or any camera and not get reviews that run the gamut. "The D3x replaces medium format, or noting replaces medium format and usually there is some 200% pixel crop of a wall, or eye to prove it.
But obviously we all have different needs and circumstances, which is why one person says "my p25 shoots great 800 iso and the next person says they wouldn't dare move a medium format back of 200 iso.
Once again, if your a professional working on deadline it just doesn't work that way these tests show. When you have 45 seconds of backlit direct sunlight left in the day, the production brief calls for interactivity and movement then the camera that is useful in that situation is the one that will hold focus and allow you to get the shot.
This doesn't mean that a D3x is better or worse than an H3d, or a P45 is not a good camera, it just means that the only way you can compare is under pressure in the actual conditions you shoot and at the end of the day, nobody you shoot for is usually looking at dynamic range that is 4% bettter, or if there is some chorma noise in the shadows. They look to see if you caught the emotion, got the frame needed and if it's in focus.
I know deep in my heart that the cameras are only about 15% of the equation on shooting a pretty photograph. We can all talk this to death, shoot 200 color charts, compare noise and DR until our eyes bleed, but when you sit down at the computer to build that first web gallery I can promise you image format, file size, DR are the last thing you will be looking at.
Medium format does have a place, though in reality the dslrs are getting very close to covering their territory, but for most of us we have and always will shoot multiple formats.
A medium format camera with a ccd is not going to focus as quickly as a dslr, offer the same versatility, or be as cost effective. A dslr just doesn't tether as easily as a most medium format backs, doesn't have that ultra crisp sharpness out of the can (as long as it's in focus).
Still, once you get down to the post production of a major campaign, the camera gets forgotten very quickly.
Go to this site, http://www.portusimaging.com/
and click on portfolio, then case studies and tell me which image was shot with which camera and once you get to final, which camera made a difference.