You're quite correct about the ATH-M50's they are just 2.0
I thought the Logitech G35's were decent for their Faux surround abilities but I found that they got hot pretty quickly and weren't as clear as my headphones. I hear that the razer megalodon's are of similar quality and you may wish to check out Tritton and Turtle beach.
I wish I could be of more help on the headsets but I've only ever owned a couple pairs and I was never head over heels for either of them.