Excited at this news! I have several Samsung external drives starting from the first ones (T1) and going right up to the T5..... And I, too, adore my T5s. Terrific little devices! I had suspected that something new would be announced this fall and was thinking it might be a Samsung T7, but this is even better news! Right now I don't have one of the 2018 MacBook Pros, but it is on my agenda for the not-too-distant future, and I can easily imagine one of these interesting new X5s as a companion eventually..... Although at first disconcerted by the news that the X5 is not backwards-compatible, it occurs to me that it would still be simple enough to plug in a T5 at one port of the machine and the X5 in another port and easily transfer data, and of course as time goes on one would use the the x5 as the primary external drive and then as needed copy data it had retrieved from the machine from it to the T5 for ongoing storage and backup......
I'm addicted to external SSD, no two ways about it! I can already predict that not long after I finally do get a 2018 MBP that there will also be an additional expenditure for the X5.....