I just traded in about a dozen pipes. My cost outlay on the lot was probably about $3,000.00 new over the years. I got a decent credit from a retailer and my selection of replacement pipes was 2 Castellos. Very literally, I had a moment smoking one of these pipes (that I paid over 400 dollars for, so this isn't a "expensive = better") and I realized that I hated the pipe. It gurgled no matter what, spat hot horrible juice out the stem. And this is after drying some tobacco and carefully packing and smoking for about a 1/2 hour. (I took the same tobacco, undried, rammed it into a reliable Radice and had a perfect smoke, no fuss, no gurgle, no juice). So ... that first pipe isn't working for me. Could someone else love it? Maybe. I don't care. Whether this is objective or not, that pipe smoked like a dog turd for me. I have 3 Castellos, they all smoke perfect, every time. So... I bought more.
How could a Castello smoke better than some other pipe? Well, open the suckers up. What you find is that Castellos have very smooth airways, pretty much constant volume, no huge gaps inside, they pass a pipe cleaner (which merely means that things are lined up reasonably well). There is very little turbulence inside the pipe as you smoke, meaning very little condensation. The stems are acrylic so they never taste "off" (and some of us can turn a vulcanite stem brown in 2 minutes and get a sulphur taste out of them).
So there it is. I'll pay 300 bucks for a pipe that is built in a way that I agree with, that smokes nicely and behaves well with every tobacco I use. It's not magic briar, it's not some stupid gimmicky apparatus, it's just a carefully built pipe, and it out-performs less carefully built pipes. Nothing to do with the stamping or provenance. Just physics.