The Walker cameras are rock solid.
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A major plus over the dedicated 617 cameras is the option to use large format lenses without the expensive dedicated mounts.
Also of course you get tilt/shift/swing movements on the front standard.
No 4x5 is as rock solid as a dedicated 617 camera with a helical focus. Only if need lens movements may one be needed, but then... why not go with a 4x10 or larger? A Shen-Hao with a quality lens will do same job as an Ebony, but cheaper and cheaper accessories. A camera is simply just only a box with adjustments of lens and between it and the film.
With Fotoman there are no expensive dedicated mounts. They are all affordable and exchangeable.
I tried 617 roll film holder on my Shen-Hao prior to buying my Fotoman 617. The 617 roll film holder was a mess in non simplicity of mounting first focus adapter, then roll film adapter. AND, it was no less weight to carry than I have now with my Fotoman 617, actually it was bit more with roll film adapter to 4x5...
As indicated in an above post, simplicity is what is good for photography thus so we can do more photography, or at least focus on subject when we shoot instead of on the equipment.
Check out Peter Lik @ peterlik.com and do a search of him on youtube.com. The bulk of his photos are from an old beaten up Linhof 617, no lens movements. He appear to recent also quick have gone through Dslr -> Hassy Digi -> P45+ on Alpa. In landscape photos, per judging on the BBC video of him on youtube, he sounds as the in $$$ most successful landscape photographer ever. No fiddling in field, merely simplicity.
After above, ask why you need complexity when you can get more or less same photos with much ease for much less $$ than some of suggestions by posters above?
A used Linhof or Fuji works, but a new Fotoman is cheaper. I have no experience of using a Linhof or Fuji, but my Fotoman is a precision carved out of metal, far above the quality I have seen from e.g. Gaoersi. The very important in choice is the choice of lens, and to pick a quality Schneider or Rodenstock, and to research for which is a very sharp and correct focal length for preference. Check Ebay, some go for very cheap. For focals, for 617 the popular seem to be 72mm, 90mm and 105mm, and as second focal 180mm. It depends on our eye for preference. The 90mm is my favorite. Why? In 35mm equivalents, it equals about 22mm in width and 45mm in height, two of my very favorite focals that I have for my other cameras as well.
Do bear in mind that a 624 camera is bulkier to carry than a 617, thus you will carry it less often. A 612 is smaller yet than a 617. I think the important in choice is the preference for format between them, and compromise.
B.t.w. Fotoman also have its "Shift Adapter" for lens rise and fall, but... it adds half a kg extra.
Best of luck on your choice, and above all on photography.
Regards
Anders