The 2 Recievers are very similar quality and power wise. The main difference is going to be the sound. The Yamaha will have a brighter, more defined and crisp sound. The Pioneer will be warmer and full sounding. Both have auto Calibration systems. The Yamaha is going to have bigger selection of sound fields. Both are quality products. I bought the Yamaha because because I have a good friend who is an engineer with Pioneer, told me the Yamaha would be his choice. His main reason was reliability. He said, as a dedicated piece of HT equipment, the Yamaha would be more durable to the hours and use it would be put under. If I was going to use it for music only, he recomended the Pioneer, mostly because he likes the House sound of Pioneer. Go figure. I could have picked up eighter reciever for under 400 through him. I like both, but prefer the sound of the Yamaha. I did not get into the specifics of what makes the Yamaha more reliable, but I listen to this guy since one of his resonsibilities is to evaluate competitor equipment for the designers at Pioneer to have benchmarks to work against. He has had the whole Yamaha line apart and evaluated piece by piece personally. He also recomended the Dennon 2000 series AVR recievers, and I might have went that way, but did not have the access to the pricing he could get me on the others. I hope this helps.