I don't really listen to music much on the iPad, so it's inconsequential to me. Music would be one of the first things to go if I needed more space for movies on my 64GB iPad.
I have the Apple headphones, but not the stock ones...the ones with the inline mic and volume control that are about 80 bucks. I'm not really an audiophile and when I'm listening to a song at medium to low volume, the highest I ever listen on the iPad, it could 65kb for all I care.
I have a remix of a song from the Book of Eli sountrack that for some reason is 64kb or something, can't tell the difference.
But then again I was an artilleryman for 3.5 years.
My entire music collection is only 8GB and that's WITH all the crap my wife listens to added in. The music that I had before we got married was maybe 5-6GB.
I would never dream of having 32GB worth of music on an iPad, that's what an mp3 player is for...but that's just ME, obviously just my personal feelings. Obviously you are much more into music so I can see why you would use that as your main staple for the iPad.
For me it's videos, then apps, then photos, then music last in my orders of priority.