I have a chance to get a pair of these liners,are they worth getting and using them in my old Lange RX boots?
Tough question. Depends on what you're looking for. I'm skiing a set, and they are firm-ish, comfortable, and warm.
But they do not have the precision of something like an Intuition.
CAVEAT: IMO, these liners are about 3/4" short of the height they should be (using my Raptor liners as a reference). That bugged me the first day. By the third day, I'd kind of forgotten about it.