I'm pretty new to all of this too, but from what I understand.. if you're not going to run a seperate amp, you need to find speakers that have a higher sensitivity.
More "sensitive" speakers require less power input to create the same volume of sound output.
So afaik, look for speakers with higher sensitivity 90 dB or higher.
I'm doing a similar thing, and someone suggested the Infinity Reference line to me. Medium cost, decent sound, and higher sensitivity.
But like I said.. I don't know much about this stuff.. hopefully some of the experts will weigh in.
P860MP is a better unit. IMO the P8MP looks gaudy, and the one knob feature, as Jexx pointed out, is a bad feature.
Travis you are on the right path. Remember, if you spend money on quality products you get quality sound. Reference line is nice, but if you can spare a few more bucks, the Kappas series is even better. Also look into Polk db series, I tend to prefer Polk over Infinity.