You’ll be very happy with the scan quality, it has a good Sony Pregius imager with a low noise floor and a very good backlight which also makes a big difference.
I have not the liberty to say much about the scanning contact for obvious reasons, but you are right with the sensor. The examples I have seen were so good that they have convinced me. I was thinking about 4K for scanning in the first place, but decided going for this opportunity. It didn’t make any sense to me not just because of the print itself, it would have been more expensive and I couldn’t justify it myself(again we are talking about the difference between 3,5K vs 4K). While I gained more experience about the details of scanning since then I think even more that it was a good decision now. But feel free to put some perspective of yours in it. It is just interesting to speak about details and differences on technical specs 😃