Hello Allen, I was not aware of the DEF models set, is it for the Academy kit? I have seen the Legends stowage set and the MK 1 designs etch set.
I agree with you about the Turkish Altay, it would be a nice addition a modern armor collection:

...but as it is still a final prototype it will probably be awhile.
The Leopard 2SG used by Singapore:

...might be something we see a little sooner, since there are so many companies with leopard 2 kits out there to use as a starting point.