My iPod Classic no longer has good enough battery life for what I need it to do. So, I was recently debating whether I should buy another Classic or an iPod touch. My music collection is about 80GB, but I'd have a lot of use for the capability of the Touch in other areas. But, I was concerned about a touch sounding like crap like my iPhone.
I figured I'd share my thoughts after not finding much comparison on the internet. Summary is that I got a Touch, and I'm very pleased with the sound. It's actually better than the iPhone, and even superior to the Classic. I know nothing about the specs of each amp, but through my Monster Turbine Coppers, the Touch is the best sounding of the three. I'm very happy and surprised with the sound quality of the touch.
I have recently bought a Nuforce iDo, and it's a very impressive product as well. Sound quality is definitely improved over the internal amps of any of the players. But, I'm glad to have the Touch sound quality when on travel.