av1963 wrote a review of Lange RX 120 Ski Boot - Men's on January 20, 2013
Familiarity: I've used it several times
I'm an aggressive advanced - expert skier.
6' 1" 205lbs.
I've used the RX 130 and the RX 120 for 4 full days in each.
Very little difference in flex, but the 120 is a bit more forgiving and slightly more comfortable.
I believe the biggest difference is the power straps on the 130. I swapped out the straps and noticed the 120 feels about as stiff as the 130.
I'd say if you're you're a hard charging aggressive skier, either the 130 or 120 would fit your bill, with the 120 being a bit more forgiving and comfortable without giving up any significant amount of performance.
Either way, this are top notch boots from Lange. Comfortable out of the box.
* Be sure to get the correct size, maybe go a size smaller because the liners will pack out quickly.
I'm a happy camper in the 120s!