What does the BK watch correct?
TM, the bk version has his custom datewheel overlay with improvements in centering and size on certain numbers. He also fully presses the crystal so it sits even with the bezel insert and reduces the chance water will enter the case.
I also recall on any DSSD purchased from him in the last two months he started installing better gaskets to improve water resistance as well.
The biggest thing really is the gen swiss eta movement or sellita movement he provides with his offering.
There are other things like the correct 10 on the insert which is not exclusive to him since other dealers offer this same version.
In all his offering is around $100 bucks more than other dealers ultimate versions, is it worth the extra money.... I guess each person will have a different answer, but to me I think so since he is stateside and one of the best dealers to buy from.