Silk Purse Out of a Sow's Ear?

I recently went on e-bay and bought a pair of Polk Monitor 30 speakers for a friend, but it took about two weeks for them to be delivered (I had them shipped to my house), and by that time, his son had given him a set of speakers. I figured I'd just re-sell the speakers or possibly keep them, depending on their sound/condition. When I opened up the box, they were in like-new shape, which was a big shock ($76 shipped). I hooked them into one of my systems using a Parasound P-5 preamp and an ATI 1802 amplifier, along with a Bag End Infrasub. I was blown away by how good the little Polks sounded, very smooth but articulate, with excellent pacing. I had just removed a pair of Totem Mites from this system, and the Polks were a big improvement, to my ears. The mid-range was flat-out luscious, with vocals and stringed instruments bordering on being mesmerizing. Everyone knows that most higher-priced speakers won't sound good if you cheap out on the electronics, but it is amazing to hear what slightly upscale gear can do for bargain-basement speakers, or did do in this case. I had never heard this model of Polk speaker before, so I went into this with low expectations. My point is that maybe we get caught up in the idea that more expensive automatically translates into better, and it doesn't necessarily have to be that way.