Replacing Nano with iPod for Best Sound

Despite the sleek, sexy design, I have decided I don't like my iPod Nano. It sounds terrible, has a wimpy amplifier, runs out of power quickly and clips offensively as the battery declines.

Perhaps I am out of date or a little old fashioned, but on reflection, I don't care if my iPod is smaller than a wristwatch, how it interfaces with tube amps and electrostatics, or whether or not I can store 50 million songs, TV shows or phone numbers.

I am not interested in sending it off to be modified for hundreds of dollars or connecting it to geeky, tweaky AC powered components on my desktop.

I don't want to "dock" it anywhere, use it in my car, take it to friends parties or fit it into the sleekest, slimmest of shirt pockets.

No, I simply want to use my iPod as a reasonably portable device - in particular when commuting and working out in the gym - while sounding as good as possible, and I dont mind if the device or my headphones are a bit clunky.

Therefore, could someone therefore please update me on the best iPod for portable use only:

* Generation V and VI or the newer "Classic" iPod?
* Which iPods can handle uncompressed or lossless best?
* Which lossless format is best for sound and battery life?
* What headphones can be driven directly and sound best?
* While remaining portable, has anyone experimented with a battery powered external amp and/or line out cable?

Thanks for ideas. I look forward to enjoying music again on an iPod.

Regards,