I don't think the OP really "hammered" on Parts Express. I think he's just looking for the higher end of DIY speaker parts. I have purchased several things from Parts Express and they are an excellent company. Their "Dayton" series of drivers are very excellent for the money and sound damn good for what you are paying. They are not the highest resolution parts, but they definitely don't sound bad. I have used other types of drivers from Parts Express when I need a specific type of driver. They do carry Janzen caps which are also good as well as Solen caps. They also have an excellent level of subwoofers and full range drivers.
But they don't carry stuff like Seas, Accuton, ScanSpeak, Mundorf, etc.