I am not familiar with the Pioneer models, but just bought the Yamaha RX-V777BT. I've got some in-room frequency responses to work out. Just got around to playing with the 7-band PEQ and am really pleased with the flexibility and results. Pretty much have gotten my semi-flat response curve worked out. There is no "sub" PEQ on this model. There are allowed band adjustments at 30, 40, 50, 60 and 80Hz, but only for the 7 speakers, not the .1 (or .2). I assume this would be helpful if your speakers were set to "large" playing full-range. For sub EQ, you'll have to accomplish that through an outboard EQ. The Art 351 EQ (~$120), for example, has about 7 or 8 usable bands in the sub-range. I've got 2 of that are waiting on cables so I can try them out.
As for the YPAO on my model, it's not perfect but gets a lot things right and saves a bunch of time. Distances seem to be accurate. Here's a few things I had to tweak afterwards: Levels. I didn't agree with center channel and sub levels, but they were close. Maybe just my personal preference. Speaker size. It set all speakers to large. Even though my towers can play low, I wanted my subs to handle the sub-60hz stuff, and my in-wall surrounds definitely shouldn't be played that low at high volume. So I set all speakers to small, and set my xover at 60HZ throughout.
After all is said and done, all you tweakers out there (including me) will find yourself dialing your system in to take over where the YPAO left off. BTW, get the free AV Controller app for your phone or tablet. It's awesome and allows for quick and easy system tweaks, and other cool stuff. The on-screen menu is pretty good, and you'll need this along with the remote for the manual setup.
My older HK-AVR635 receiver had a little more muscle and about the same sound quality. But the connectivity and versatility of the Yamaha sold me. As far as the iphone app, I wouldn't want to be without it now that I've experienced it. So far, I am very happy with the purchase.