Liquid Glass's key ingredient is a "crystal clear carbon", which dries rock hard. Klasse is an acryllic. Klasse SG can be tempermental to apply. I've never tried the LG, but I've also read that it can be applied in sunlight, something you would not try with Klasse.
Thatbeingsaid, I love my car, which is wearing 3 coats of Klasse SG, and now only has to have a weekly wash and occasional QD, for the next 6 months.
Jeff Laughhunn