Whether they are an improvement at all is completely subjective. I think the AKG's offer a different sound altogether. Where the Senn 600 sounds warm and laid back, the AKG 701 sounds more clear, slightly lean and more midrange centric. The AKG also sounds a lot more spacious.How much of an improvement do you think the AKG's are over the Senn '600s, and in what areas?
I am actually currently in the process of changing headphones again. I'm hearing good things about the Denon line