Hey head-fi. I am posting this on behalf of one of my friends. He is looking for a pair of closed-back over-ear headphones for traveling. That means very good isolation, no sound leakage (good seal) and comfortable for long periods of time. On top of that, he has a wider head, if that is to be considered. Preferred signature is unknown, but I will get it as soon as possible as well as his price bracket. However, I am also interested in buying a pair of headphones that match this criteria. My preferred signature would be that of my he-400's with a bit less treble and bass (so more neutral while retaining a light v, preferable with a larger sound stage and lots of detail). I am looking in the sub-300$ range (that also includes 300$ used), but suggestions in lower brackets would also be appreciated for my friend. Thanks!