I think converters are a crucial part to how guys like Andy and Zeuss get such clear sounds...yes, they have impeccable live rooms as well, but if you don't have ultra-clear converters to take advantage of the acoustic spaces you have...you're fucked. Obviously, Andy can use any fucking gear he wants (he used his Digi 002 when he was tracking the newest Exodus) and he will still make it sound absolutely amazing. But I definitely think high-quality converters factor in to what sets guys like Andy apart from the competition.
At the same time, for average guys like most of us, who are recording in their basements/garages/bedrooms, converters probably won't do much since if anything they will expose the inadequacies of the spaces we are recording in...