I don't know the answer to your questtion. I don't know many people who would buy all 3 items to compare them, because that would be the only way to get an idea...
I own a 20GB iPod and it has all my music. I use it at home when I do yard work or chores, in the car as a music player as it's plugged into my power amp and sound system, and at the office for music as well as for data transfer. I also use it to record interviews on the phone with the iTalk attachment. I'm very happy with it. That's all I can say.
Ball's in your court now!
