Bryston SP2 - what's the improvement over 1.7?

Seems like it's almost same...

still no DPLII while it's 7 channel pre/pro, and no HDMI...

What's the point of SP2 over 1.7?
Have you gotten any feedback on this subject? I am considering upgrading SP1 to SP2 and am looking for input from anyone who has compared the two.
I upgraded from the SP1 to the SP2, and the improvements are in the surround decoding. There is much more clarity and it is much closer to the original SP prototype that I got to listen to quite a few years ago.
When listening to 2 channel playback do you feel there is a difference in sound quality?
The main difference between the SP 1.7 & 2.0 is a new digital chip- analogue pre amp is the same. Refer to Bryston site: