I'd also like to add that after almost two month of sporadic use with the 8600, I am happy with its performance. It works well and is well within its specifications.
The software is still a disappointment and I have gotten used to the cheesy rotary encoder.
So despite my dissatisfaction with the feel/build quality/software, I can recommend this load to someone who needs/wants integrated USB and a warranty. The 8500 is still probably superior in total value, though.
Can't wait to see the pricing on the Itech equivalent of the 8600.