I found an email address for Masterfoods and sent them a post yesterday asking if a dark choc Twix was a possibility.
All I got back was the usual " we consider new products constantly but cannot divulge what we might do due to our competitors, blah, blah'
If you don't tell me, do you think that will stop the others making their own varieties? Trade secret, my arse!
The would not commit on the comeback either.