Very good phones for the price, IMO
Very easy to listen to with no fatigue for me. I don't really listen from my phone, but almost always from my computer or from my XDuoo X3 II that I carry with me. Haven 't carried it with me on the plane yet, but I've been flying a lot so may try taking them with me once soon. Hearing outside noise isn't a negative for me as I like to be able to know when something's happening around me.
I listen to a lot of vocals, strings, piano, and horns (classical, jazz, pop) and not a lot of heavy bass. To mirror what others have said, to me these sound pleasantly warm with a good amount of detail and clarity, but not as much as some others. Despite some nit picking, it's a very pleasant listen for me for my typical music, but with quality and defined enough bass when it needs it. Lisa Hannigan's voice is always lovely, but particularly nice with these ;)
Also have Harmon Kardon CL headphones. Those have more impressive detail, but for certain things can be a bit cold, but I like those as well... just different from the Purplehearts
Would recommend to a friend.