Appreciate the info very much - now I just have to narrow it down to the 245/345 or the 445/645. I've got a friend at an electronics store that can cut me a break on either option, though my untrained eye can hardly justify the price differences between them as the features on paper are nearly identical. I assume its mainly more, clean wattage as you move up the teirs? I really wouldnt mind spending a bit more on a nicer model if it translates to better sound.