Hi Michael,
I've been working with Phase One and Hasselblad systems as a freelance DIT for more than 6 years. I also work at a rental house that happens to be a regional distributer for Phase One, amongst other brands. We used to carry Hasselblad systems but we got rid of them about 4 years ago because of how unreliable they were and how bad their customer support was. I have access to pretty much everything that Phase One makes and at least 4 XF bodies at any given time. I also regularly work with 4 photographers who own Phase One systems. I may also be a tiny bit biased.
I would like to point out a few factual errors in your blog post as well as a few subjective observations that I've made.
Auto Focus: Having used at least ten different XF bodies with many different lenses and backs, I've found the autofocusing to be largely consistent if you put the known limitations into consideration. The amount of people online who claim that they can't get sharp images using the XF really surprises me. In my experience, when an image appears out of focus with the XF, it's usually pilot error. I've seen photographers using extremely low shutter speeds with natural light while handheld, shooting a moving subject while they themselves are moving, and thinking that "focus recompose" means they can take a few steps back and to the side while recomposing. Assuming you have a rough idea of how focusing works, you probably have faulty body, lens, or a bad combination of back, lens and body. One of the main reasons a lot of professionals I work with go with the XF and IQ3 is for the 5 year warranty and uptime guarantee. If you have any issues with anything at all (even if it's completely your fault), Phase One will make sure you have a working system in your hands within 24 hours and in our case, we would swap your faulty system with one of our tried and tested rental units until the loaner arrives from Copenhagen. I generally find that people who put down over $30,000 for a camera system will not hesitate to take advantage of this feature. It baffles me how anyone when faced with AF issues after spending that much money, would choose to go online and complain on some random forum instead of contacting their dealer immediately to get a replacement. In our entire region, we've only had one body returned to Phaseone to have the focusing system recalibrated and two situations where the lens was a bad copy, one of which was sorted with AFMA. Regarding focusing in low light, as others mentioned, the XF should turn on the AF assist light by default if it can't focus using ambient light. You must have had it turned off. As for "True Focus", try putting your Hasselblad on a tripod and pointing it at something still then initiate autofocus a couple of times. If you look at the focus scale on top of the lens, you'll notice that it will refocus each time at a slightly different point even when nothing is moving. This level of inconsistency might not make much of a difference when stopped down but try nailing focus with the 100mm at f2.2 on the H5D-50c. The XF, on the other hand, won't even attempt to shift the lens if nothing moved when you refocus and focusing with a 150mm at f2.8 has never been an issue for me. Another great feature that's been introduced in the H5D is True Focus 2, which seems to just take twice as long to focus as the H4D without actually being any more reliable.
Image Quality: Knowing you only had 7 out of 200 images in focus, I'm not surprised that you consider the images coming from the Phaseone to be soft. What constitutes as "sharp" nowadays is very subjective anyway. I know some photographers who are more than happy with images shot handheld with the old Canon 24-70 at f2.8 on a 5Ds at ISO 800 and others who won't accept anything not shot with Rodenstocks at f8 with a 60mp Dalsa. A few photographers who switched from Hasselblad to Phase One this past year mentioned to me how what they thought was sharp on their Hasselblads looks soft now in comparison. A lot of others couldn't tell the difference and don't really care. I personally did a side by side image quality test between the IQ250 with 645DF+ and the H5D-50c when it first started shipping. In terms of sharpness, the images from the Hasselblad looked great until you put them next to the ones shot with the Phase One at equivalent focal lengths. That was especially apparent when comparing the zoom lenses and pretty much any of the primes when shot wide open. The only Hasselblad lens that could actually out resolve the 50mp sensor is the 120 macro. As for high ISO performance, in my side by side testing I used Capture One to process Phase One files and Phocus for Hasselblad. The default values of the two different processing engines gave different noise characteristics but I managed to get them to look quite similar with a bit of tweaking on Capture one. With the right settings, Capture one is able to remove so much noise from the highlights to the point where you can't really tell the difference between ISO 100 and 6400 unless you look closely at the shadows. Phocus seemed to sacrifice a lot of detail when applying noise reduction and it required playing around with the sharpness to get a lot of it back. When noise reduction is turned off completely, both cameras gave very similar levels of noise (it is the same sensor after all). I also noticed that the time that Phocus took to generate previews of high ISO files was significantly longer that Capture One and the time increased exponentially the higher the ISO was. I think it's a bit unfair that your only comparison is between two completely different photos, especially considering that shutter speed contributes a lot to shadow noise on both cameras and having details in your photos also helps.
Ergonomics: This is obviously very subjective. I just wanted to note that the touch screen on the XF can be locked by swiping to the right and tapping "touch" and the one on the back can be locked by tapping the the little speech bubble on the bottom right and then tapping the key icon. The interface is designed to be almost completely usable without ever touching either screens. The only thing you can't access without touching the screen is the new focus stacking, HDR, and timelapse tools that were introduced last month.
User interface: You mention that mirror up on the XF has to be put up for every shot. This is simply not true.
Flash Sync: As Jeffery mentioned, all the lenses sync up to 1/1600 with the exception of the 40-80 and 240. They're designed to sync at 1/1000 when stopped down but I notice that you can get away with syncing at 1/1600 with just a bit of vignetting on the 40-80.
Reliability: As I mentioned before, Phase One are confident enough with their system that they're willing to include a 5 year warranty and uptime guarantee with every new system. Good luck getting that from Hasselblad. I've seen Phase One cameras working smoothly in a quarry where the temperature exceeded 60 degrees celsius, an indoor ski slope where it was -15, crazy sand storms, water park rides, in underwater housings, and on top of the tallest building in the world. In all theses situations, the photographers were confident enough to not bring a backup.
Finally, you mentioned this:
I have Elinchrom’s amazing Hi-Sync technology, which allows me to sync strobes at up to 1/8000th second with my Nikons if I really need to freeze motion using strobes.
I'd like to point out that your shutter speed does not make much of a difference when you're trying to freeze motion using strobes. It's your flash duration that matters.
Mellifluous felicitations,
Ahmed