G'day,
Edwin made a really amazing observation in the post below, which is Lange to use different technologies to ensure shock resistance. Not just different movements come with INCABLOC or KIF shock protections, but at times the same movement base to be fitted with different mechanisms!
Well, one really doesn´t stop to learn 
I thought some closer views might be interesting; the 2007 models seem to show a preference for the KIF mechanism:
L 921.4 (Grande Saxonia)
L 941.1 (Saxonia manual wind)
L 901.4 (Little Lange 1 "Soirée")
L 931.4 (Cabaret "Soirée")
L 034.1 (Lange 31)
For comparison:
L 041.2 (Richard Lange)
L 921.2 (1815 Automatik "Cuvette")
I´d guess there´s a specific reason behind, so hopefully more on this later!
Greetings from Germany,
Peter