Got mine about 3 weeks ago from Costco just for my 2.1 setup. After doing multiple experiments with MCACC + using CD quality digital source, I can say without a doubt that Pioneer gives me the best stereo experience in my music room. I have used 3 different receivers (vintage receivers and newer Yamaha) and preamp + amp setup in the same room with same speakers + sub setup before. I also tried the same speakers + sub setup with Onkyo receiver in different room with proper Audyssey setup. I would say Pioneer beats them all by a large margin. Connect the Pioneer directly with high quality digital source, the music details are simply amazing. Music is life like, more 3 dimensional. With MCACC, my room modes issue is also solved. Now nothing rattles even on higher volume (I like to listen to volume in the range of -8 to +3 in my small room).
When I first got it and done my initial full auto MCACC setup, I was not too happy with the sound quality. I thought Pioneer sounded too thin and bright and missing the mids. However, by doing more experiments with microphone placements + speakers and subs angles + speakers settings, I finally found the sound I like. If you are still looking for the best music sound, below are my findings that might help you:
1. Microphone placement is very important. I found that moving just by 2 inches up, the MCACC adjustments would change a lot both in the frequencies that MCACC applies the filters and how MCACC adjust the EQ. Moving 2 inches back, the MCACC changes its settings again. I would suggest using a camera tripod to hold the microphone and start by placing the microphone at exact ear level of where you sit, then adjust from there. For example, moving the microphone up a couple inches so that the microphone is exact height as my ear canal helped with the bright sound.
2. Slightly adjust the angles of the speakers and even the sub (so that it is not parallel to the side walls as suggested by the manual) would again change the MCACC readings. For example, before I adjust the speakers angle, MCACC always place a filter at the 60Hz range. After the angles adjustment, MCACC no longer places any filter below 100 Hz. I really like how MCACC could show the result of changing speakers angles almost instantly. That is pretty handy in discovering how to solve the room mode issue.
3. Using different speakers setting in the setup menu would also change the MCACC readings. For example, after doing initial full auto setup, I manually set the speakers to small, and then used "keep SP system" and run auto MCACC again. The reading was different than original full auto setup's readings, even without moving the microphone. Without moving the microphone, I manually set the speakers to large and sub to plus, and then use "keep SP system" and run auto MCACC again. The reading was again different than using "small" for speakers and "yes" for sub. The "ALL CH ADJ" readings were very different between the two speakers settings. It looks like when I select "large" for speakers and "plus" for sub, MCACC wound include the sub's effects when calculating the EQ for front speakers. For example, my sub is placed in the front right. For the "ALL CH ADJ" EQ type, MCACC would boast the 60 HZ range for my left front speakers and trimmed the 60Hz range for my front right speakers. I ended up liking "large" and "plus" for speakers setting and "ALL CH ADJ" for my EQ type the best.
Wish all of you happy listening!