It comes down to personal choice at the end of the day,i have a set of Koss UR30s that came with the Minelab Sovereign GT that i must say a very comfortable being circumaural but the lack of a volume control can leave them slightly piercing in the ears at times when i run over large targets etc. The next move if i'm thinking of an upgrade will probably be a set of Predator Excelsior headphones.They run at 80ohm and are built into the ear defender Peltor designed unit.
Cheers
Stephen