I'm currently using 2 X1s, combined with turntables for DVS and an Allen & Heath PX5 mixer. Works great with Traktor, but I don't really like the X1s (I used an S4 Mk3 before). I miss the screens, as I now have to look at my computer a lot more. The sadly discontinued D2 offers all the goodies of the S4 in a more elegant package and better form factor (same depth as my mixer and 1200s).
As the X1 and all in ones like the S4 Mk3 are still available for sale and presumably share internals with the D2, my hope and expectation is that the D2 is going to be supported with Traktor software updates for as long as those devices. But before I go out and buy a pair of second hand D2s, is there anyone who has information or an opinion on how long we can expect the D2 will be supported going forward?