Hey Proof - certainly hope the boots are going well!
I definitely didn't find them too stiff, but even though we are about the same size, I like a stiff boot. I found the flex excellent and very smooth compared to my Dobie Pro 130's (my gold standard). I like to compare the Dobie flex to a feeling as if I've stepped on the gas pedal of a porsche - just surges ahead.
Have you considered popping a rivet and taking it down to 120 for a day? Especially when it's cold. Maybe just give it a try.
I remember having to take out a rivet in the back of my Lange WC's on -30C GS days up at Tremblant.
In this case, your loss was my gain. Love the boots!
With respect to firmness, what's your take on stiffness compared to Dobie 130's? Again, I'm not so concerned with forward flex stiffness, more with lateral stiffness and support. They just fit nice and snug around my shins. You mentioned "stepping on the gas pedal" and I like to feel some pressure on my big toe...the boot enables that feeling pretty well.
One aspect of stiffness that's not been discussed in depth here is the 3 different boot inserts that are provided with the Redster 130's. I had been skiing with the mid-stiffness (GS) flex, and, skied yesterday with the softer DH flex. It does soften the boot a touch, but, it was a very warm day, so there were two factors in play, maybe three as the snow was just so soft. The Sl flex insert is very stiff. Anyone who thinks the boot is soft or seeks more stiffness, needs to insert the Sl flex.