I'd recomment Beyerdynamic DT770.
Link
Great for mixing, quite comfortable and they isolate pretty well.
I wouldn't recommend PROline 750 because these are the most uncomfortable headphones in the industry, GUARENTEED.
They are just a torture to wear, believe me.
if you do go for the 750's, then beware of their bright nature, they could be very unpleasant if not amped properly.
Also stay away from Grado and Sennheiser as they are open cans.