At one time, maybe four or five years ago, I skied with a young man for a few runs who was on the U.S. D (Development) team,
who was on a pair of Lange RS 140 LV at first. We rode up on the lift together a few times, and he was A/B testing them
against a Head RD boot (one of the plugs? (and a few other boots also), that he said was a bit stiff for GS for him,
whereas the Lange 140 was his likely GS boot, at least for many situations (softer flex than his SL Head boots).
He said that for him, the main difference was the race lace up leather lining, which appeared to be thinner but
sturdier and better fitting - often, for many, including for this racer (as he described it). He also said that he had a pair
of RS 130s LVs down at the base with his other stuff (other skis, bags, other boots), which he was also testing, and that, for him,
that 130 was maybe just as good, maybe better, for GS, as the 140 LV, except he used the leather liner from the RS 140 (LV)
boot in both, instead of the stock 130 LV liner.
I've had the impression he said that the 140 back then might have been the same or almost the same outer shell as the 130 - at that time;
but I don't really know. It was not something I explored further, and I figure things can change year to year anyway.