And, you know what? The quality is really good ... I am going to borrow the line cord from the Weller to put on it, to save having to rewire a Hakko-compatible connector onto the base. So, have taken it apart, and I am very impressed. I'm so confident I am going to 1) buy another one and 2) buy some bits. That is the other small difference .. Weller ETC bits are £6 each, and Hakko bits are ... um .. let's see ... pack of ten for £4.39.
Of course I will have to re-calibrate, since Hakko use a PTC with some strange characteristic. I took this (room temperature, it's meant to be) partly to show off the TIL311 LED displays. HP don't make them any more - or at least I don't think so. These came from a project at work in about 1980; they've been sat in a parts drawer since then. I use them on odd projects that come and go .. always put them in a socket so they can get re-used. They are partly why I had to put a switch-mode PSU in the Weller controller - poor little 7805 nearly caught fire.