The 6G does not have coupling caps on the output, so it is impossible for him to compare the two on even terms, unless he was to compare them both using apples native line out... at which point it has nothing to do with the Red Wine Audio mods.
I'm with swt61, the 6G sounds like a great solution if you don't want to mod your iPod. I'm pretty sure there will be lots of comparisons between the 5.5G and 6G as a 'home source' in the days to come for those who are interested in more details. Since I've moved towards a more minimal setup the 6G is definitely interesting based on its capacity and format options alone. Thanks for the technical overview Vinnie!
