After waiting a month for delivery from Singapore my programming box (same one) turned up yesterday and I can confirm that it does work for the 120A ESC. The number of settings available is more limited than with the Turbo ESC but as my knowledge of what they do is even more limited I'm going to take that as a bonus.
I was expecting to have to trim the lug off the plug but didn't need to although I did have to push it in quite far.