They're very well regarded as grills, and probably make a better classic grill than a Weber for grilling, but a Weber is really a 'platform' at this point - with mods to extend them in numerous ways ...
I don't think there are going to be relatively inexpensive kits for smoking, pizza, santa maria, rotisserie etc for a PK in the immediate future ...
As a plstform, being able to count on buying a replacement 22.5" Weber in the future and having your existing mods still conform to it is part of what makes them so excellent ...
I almost bought a PK two years ago, and it might very well be a better Summer grill - but I'm happy I stuck with the Weber platform all the same ...