I will try to clear up some of your confusion regarding plug boots. The reason is simple. I was once like you, eager to learn many things about plug and semi-plug boots. At a point i was almost obsessed with boots. But that was years ago.
If you have an '04 boot i believe it is an RL1, the "ancient" Lange design.
I believe that the predecessor to the current plug was built in 2005. It was called the RL11. The boot had a high instep. I had to downsize aggressively for a good fit over the instep.
The current consumer plug boot was built two (or three) years ago and was called the RL12. The boot featured a shark nose. I tried on both boots. The RL12 has a lower instep which is, IMO, much better for you than the RL11. It does not have a lot of forward lean.
Other differences from the RL11 are the lateral cant built into the mold, the zeppa which is not neutral and the liner which is now a lace-up version. There may be other differences but i do not recall them now. Those are the most important IMO.
At this point, you do not know if the RL12 is the best boot for you. IMO, it will fit your instep better but this does not mean that it will ski better. You have to consider some factors before you decide to go with brand X.
Last but not least, do not put much faith in some websites.
If you want info on plug and semi-plug boots, you should check out Jeff Bergeron's threads. He is a boot fitter who stopped posting when the new forum on boot fitting has opened. You will find info on the RL11 and other plug boots as well.
Links: 06 expert boot advice by Jeff Bergeron and the 07 thread There are even older threads but you should look for them yourself. There is a lot of info and you can learn many things about boots.
I tried on and skied a few plug boots and this is what i can tell you about them if you want a comparison.
Note: I have a fairly narrow heel, medium forefoot, mid to low instep and skinny lower leg. I weigh 160 lbs.
Atomic RT Ti 130: 95 mm last in 26 mondo, narrow heel, medium forefoot, mid to low instep, lateral cant built into the mold, lots of forwward lean. 130 flex too stiff for me w/o cutting the lower.
Atomic RT Sti 130: 92 mm last in 26 mondo, narrow heel, narrower than the Ti mid and fore foot, possibly narrwer in the heel too, but i did not measure. The difference was obvious mid and fore foot. Lower instep, lateral cant built into the shell,lots of forward lean, 130 flex was stiffer than the 130 Ti flex. The boot is a bomb and probably best left to racers.
Lange WC 150 aka. RL 11: 95 mm last (size 26), narrow heel, medium forefoot, high instep, no lateral cant built into the mold, the FL was less aggressive than the Atomics. 150 flex was a little stiff for me but with cutting it would have worked out well.
Lange WC 160 aka RL12: 92 mm last (size 26), narrow heel, medium forefoot, lower instep than the RL11, lateral cant built into the shell, less aggressive in FL than the Atomics and similar or even slightly more upright than the RL11. 160 flex required softening.
Nordica Dobermann Aggressor WC 130: 95 mm last (size 26), narrow heel, medium forefoot, medium instep, lateral cant built into the shell, toes-out stance, FL slightly less aggressive than the Atomics, more than the Langes. 130 flex is not too stiff for me but i have not skied the boot yet.
Nordica Dobermann WC 150 EDT: 95 mm last (size 26), narrow heel, medium forefoot, medium instep,lateral cant built into the shell, Fl was similar to the Aggressor, no aggressor stance, 150 flex manageable in store temps, would require softening on the hill. Nice lace-up liner.
Salomon X3 LAB Soft:? mm last (size 26) (never saw the info from Salomon), narrow-ish heel, medium forefoot, medium instep, more upright stance than the Atomics and Nordicas. No lateral cant built into the mold. The flex was manageable in store. The stance was uncomfortable for me with the rear spoiler in. I had to take it out.
Tecnica Diablo Race R H17 (150 flex): 95 mm last (size 26), narrow heel, medium to narrow forefoot, medium instep, aggressive forwad lean, no lateral cant built into the mold. 150 flex manageable at room temp, would require softening on the hill.
Oh, there is one question you could post on the other forum or on this one: which is the current design lange uses for racing? I think you would be surprised to hear it.