I'd also suggest first picking between either the Yamaha and Pio, then also purchasing the Panny xr57. If the cheaper Panny works for you, then great, you saved a bundle of cash to put towards some DVD/music/PPVs, etc. If not, at least you can rest assured you gave the cheaper one a chance.
It's difficult to compare A/V equipment until you play with it in your home for several weeks.