Ok I'll partially answer my own question after reading through another Aquia thread:
Although that chart shows an Aquia II model with a "universal height" due in Q4 2008 (aka now). So what is the difference between the Universal Height Aquia II and the Aquia III? Just a few stylistic things in the lid and shroud? Man Toto could use some help with their product organization and website.
Does the integrated trapway in the II and III explain the flushing performance drop? Anyone had practical experience with both? Does the original Aquia really flush solids better?