To resurrect an old thread, I thought I'd update you guys that I ended up purchasing the feature upgrade a little over a week ago. I reran the Audyssey calibration Friday and have been listening to it since.
I have to agree with what others posted above, it really is an impressive update. I find the Dynamic EQ makes the audio at all volumes seem more full and rich (cliche terms I realize, but it's the best way I can describe it).
Contrary to every Audyssey calibration I've done before this upgrade, I also feel that it
improves bass response in my room. Before this, I always ended up turning Audyssey off because I felt that it cut too much bass from the system. I now prefer the Audyssey sound for everything I've listened to thus far. The bass level seems to be very well-matched with the rest of the speakers at all volumes. It provides for very smooth bass that just plain sounds awesome. I'm enjoying the 600 all over again.
Dynamic Volume is also nice when watching TV, but not nearly as impressive as Dynamic EQ.
For $100, it's more than worth it.
Jason
