I've read enough about quality issues with Peterson that I refuse to buy them, but I know many love them, and thus there certainly is another view of this line. But dip-staining is certainly one of their worst quality issues. To me it demonstrates greed, pure and simple, and disdain for their customers. I've read accounts of guys needing 20 smokes to remove to incinerate or cover it with cake such that the pipe smokes well. I was told that Peterson stopped this because of the bad press.
As regards bowl coatings, I have been in the anti camp for a long time. I even held off smoking a new Ferndown because of its coating until I could think the issue through. I sent a pipe back to a pipe vendor when he offered to remove the coating. But I decided that in all probability, no matter my dislike, the coating doesn't affect the pipe's performance. I concluded this because in all of my time on the forums, no one has come forward with any data to support their position.
It seems to be all vehement opinion, just like mine
. I think it's an issue that generates strong opinions in the absence of fact.