Got my Polk speakers and Yamaha receiver all hooked up (though still waiting on my banana plugs) and it sounds pretty damn good, definitely the best sounding system I've ever had. Though everything I had prior was like $200 or less from my last 5.1 system (Sony receiver, Jensen satellite speakers) that was somehow super cheap together many Black Fridays ago to my recent LG soundbar. There's such a sound difference between this and my soundbar along with the massive directional improvement to actually having right and left speakers properly separated vs being close on a soundbar. And it's so nice having that real Dolby/DTS sound on movies. The subwoofer is real nice too, by far the best sub I've ever had as well, it took up about 2/3s of the box. The fact that it's down-firing I think makes the bass sound quite a bit better than my previous smaller subs I've had. It's also real nice having everything (PC, PS3, PS4) plugged into the receiver via HDMI, though I had to buy a couple extra HDMI cables.
It did take a bit of fiddling with all the settings on the receiver to get everything sounding right. All the Yamaha enhancer options don't really improve the sound. The speaker manual recommended putting the subwoofer crossover frequency at 120hz but that was just too much sound going to the subwoofer. I was trying to get 60hz sounding right as I'm not a big bass guy but the bass just never sounded quite full enough and then settled on 80hz. Then, I googled around and saw that 80hz is the recommended crossover frequency so I guess I wasted some time tuning it myself.