I was wondering about the "most complicated kit" title. This is certainly the most complicated Heathkit I have had the fun of putting together, with the second being a "Hero Jr." robot.. I think the later GR-2000 and GR-2001 sets with the on screen display beat this one by a bit, with the addition of several digital boards for the advanced features.
The other contenders for the complexity prize would possibly be the Heath/Thomas electronic organs, or possibly the H1 Analog Computer:
http://www.technikum29.de/en/computer/analog