the thing with Full tilt is that its a PROGRESSIVE flex. This means its smooth and all the flex doesnt come at one point and then there is no flex. Boots over time become stiffer, so if you have an old salomon boot it probably doesnt have a smooth flex and is stiffer now than that 80 flex rating when compared with new salomon boots.
Bottom line, its not the fact that their super soft that makes full tilts the full tits, its the fact that the flex is progressive, not impeded by buckles and with the extra comfy liner.
The hotdogger no 4 tongue would be a similar flex to a 90 salomon flex. The booter comes with a no 2 tongue which is obviously softer. Dont sweat it though as you can buy different tongues anyway. for instance spring skiing (boots are warmer, more flex).