I just changed my 5513 to a NDT case from Yuki because of the better case back & mid case engraving & finish. The finish of the lug is much better as well. The engraving between the lugs because it is so close to the geninue - this gives me an option to put on a nato.
The only thing from the Yuki's case that I kept was the insert. I think they are the best I have seen so far (as an aftermarket insert). One of the things I don't like about Phong is his case-back. I always have trouble opening his case back, even with a Bergeon. As mentioned above, I would not buy a complete watch from either of them. It is my experience that sometimes they have really bad craftmanship. They all use their suncontractors based in Vietnam!
Truthfully, I cannot tell any difference between a ND trading DRSD case, Phong DRSD case, and a Geninue 1665 case. Remeber people were (and probably) are selling these frankens as geninue in the grey market. Yes, experienced vintage collectors can tell the differences. But when it is a complete watch on a 93150 bracelet, I really don't think you can tell the difference. (OK - Phong's bezel is not that good)
In summary, I would just buy parts from these people (choosing the best parts) and get a 2nd hand 1601 (given that these vintage Datejust are much cheaper now) and send to The Zigmeister for assembling and services.
Flex