I have a Mares Abyss 42, and I have no need for a knob to adjust the cracking resistance.
Among the reasons why I chose a Mares regulator, was that the regulator automatically adjusts the supply of air according to the divers demands - no knob required.
And I have not been disappointed, even when diving in strong current - and having high demand of air. I have not yet used it during a winter, but I cannot imagine this would make any difference in the regulartors breathing comfort.
For me personally, the high quality, the simplicity of having fewer part and the use of advanced technologies makes me prefer Mares regulators over others brands.
But agreed, what "talks" to me doesn't have to be the only right thing for you. Take a look around, read reviews and visit you LDS to try it out.
In the end though, I do not believe that you will ever miss the adjusting knob while diving with any Mares regulator in any condition.
Best regards,
Jakob