I have posted many images in the 'recent work' thread. Please show me an example of the yellow cast you mentioned.
It may be an artistic choice and I don't follow every image posted, but your examples to me look like pink skin.
Once again if that was your artistic goal then your there, but I saw the same pink in the Dalsa sensored camera I owned as its zero daylight balance was yellow green and sometimes it was a one click fix and sometimes it was a completed repaint in photoshop.
All the backs are good, but the point of spending money on the HY6, especially if you start from scratch and don't come into it with a Leaf or Sinar back is your scrapping many tens of thousands of digital equipment just to use the camera.
If you started with a Sinar and have a lot of legacy glass your fine, If you didn't your probably rich or dig searching the net for used lens bargains.
Regardless, I have nothing against Sinar, but I wouldn't dive into one. Their marketing is very poor, the ability to find a sinar back with any camera in rental in the U.S. is almost unheard of and last but not least, the software from every report seems to be less than 100% stable.
You bleed Sinar Blue and that's fine, nothing like Brand loyalty if your into that, but for anyone to compete in the professional market with Phase and Leaf they MUST get their equipment into rental and they MUST have dead on, rock solid software without excuse and extra steps.
Personally I think the backs and camera looks like a Euro medical device in that grey/blue paint scheme, but once again, to each his own.
I don't care what anyone uses and don't make a penny from the proceeds of camera sales and fully recognize that what I need is and can be different than anyone else.
(end of disclaimer).