Daneel,
I can tell you a bit about the EQ but this is my first amp with this feature so I can't compare it with Pioneer's system.
Firstly, you can choose from 5 EQ curves and set this individually for each surround mode e.g. Stereo, Direct, Standard (Grouping of Pro-Logic/DD/DTS) etc.
The curves are None (obvious), Flat (also obvious), Normal (This appears to be the settings created from auto-setup), Front (Set all speakers to the auto-setup settings for the front speakers - not sure how this works because the EQ created for my fronts are both completely different), and lastly Manual (allows you to set your own EQ for each speaker).
Manual or Auto-EQ does not apply to Sub btw.
For manual EQ, (which I havn't tried), looks like it allows you to set gain only (+/- 6 dB in 0.5 dB steps) for the following 8 bands
63Hz, 125, 250, 500, 1k, 2k, 4k, 8k
The auto-setup seems to be a bit more sophisticated though and sets gain and Q (not sure what this is but possibly it's the width of the filter) for 8 filters at individually selected frequencies for each speaker.
e.g My front left has filters at 50Hz, 130,180, 2k, 3.5k 6k, 9k, 13k
whereas my front right has filters set at totally different frequencies.
I also see gains set anywhere between + and -9dB.
Havn't played around with it too much as I was more than happy with the improvement over the last amp after running auto-setup just once.
For info, I upgraded from a Denon AVR-2800 and am using Mission 773e, 75C and 77DS speakers with an XLS200 sub.
Not sure what else I can tell you apart from my experience this morning when checking the response for individual frequencies and plotting a graph as seen on the BFD threads, using the snapbug sinewaves.
I didn't make any comparisons with EQ on/off (wish I had now - but kids are back and hogging the room) and just took measurements with EQ on, for frequencies between 20Hz and 160Hz.
I did tests with sub and fronts on, as I was also checking crossover between them.
I was pleasantly surprised at how flat my graph was, as I was expecting massive peaks and troughs based on previous tests on the old amp with a 160 - 10Hz sweep.
I will try to do this again for the various EQ settings to see if I can see noticeable difference at those frequencies.
Not sure if the above helps, but if there are any other specific questions please ask.
Also if others have a different understanding of the above please let me know.
cheers
Gary