I personally have the Dark Lord cable you linked for my TF10 and I think it's a very good cable and a significant upgrade from the stock cable in terms of ergonomics. I can't vouch for this personally but I've heard the other cable you linked is the same as the Dark Lord in terms of quality, just with a different build.
Every time I think my enjoyment of the HD 600 has reached a plateau, it's like "Oh, you think you've heard me at my best? Please. Sit back and listen."
I was listening to Marion Meadows' Dressed to Chill album with these last night and...oh boy. Simply magical.