(Transparancy: I am the chap with a H4D60 for sale here on LL and eBay with just 597 clicks on it. Additionally I normally do not "challenge" folks here on LL for reasons learned - emotion can rule rather than science in some of the folks here.)
A prior post suggest:
"i personally don't think either H4 or H5 are worth the hassle at this point and i definitely think the X1D would be a better system."
I'll have to "challenge" that sentence.
IF quality of the image file you get is what you are after, that position can not be supported in any way!
Let's look at just the sensor/digital array.
SIZE of the wells matters along with the true bits of RGB the array can natively generate from the larger array well, and that is just science, not opinion.
X1DII: 43.8x32.9 generating 8272x6200 of 14 bit data at 50MP.
H4 or H5 60: 54x40 generating 8956x6708 of true 16 bit data at 60MP!!
Next, the H 60 series is a CCD array where the X is a CMOS (also the same sense as in the Fuji GFX 50S and the 100).
To my eye, and many scientifically based studies, there is a key difference between the two of these in the realm of image quality that is substantial to me, a landscape photographer. (most landscape photographers are obsessed with DMAX and Detail, and as one I am guilty.)
So, I'll keep it simple:
IF quality of the image is your mission that can be blow up beyond reason, the true "medium format" array (as in the H series or Phase, etc.) can't be matched.
Do you need that extra?
IF snapshots of people on the street, sports, animals on the run, etc are your "flavor", then stick with a the best Canon or Nikon, or what I have sitting on the left side of my desk right now, the GFX 50S (I also own the GFX 100 but admit it's not a "true MF" array in my opinion, but outstanding for what it is and at a price point no true MF array can touch.)
Last:
The GFX 50S with a 23mm, 32-64 and 100-200 price out at $10,393.00 with a total weight of 8 pounds on your shoulder.
The X1DII with the identical array as the GFX 50S, a 21mm, 35-90 and 120 (it has no 110, no zooms and nothing longer than a 135) is at $19,170.00 and weighs in at 9.68 pounds on your shoulder.
Now, neither the GFX 50S, nor the X1DII will give me the image I want for my work as the H4D60 will give me!
My problem is age and health, The H4D60 with a 24mm, 35-90 and 50-110 would tip the scale just over 11 pounds and I can no longer handle that extra weight walking ANY distance.