The J201 is a vintage (no longer in production) JFET transistor for which there is no modern equivalent and which is particularly sought after by builders of guitar pedals. There are hundreds of listings from China for J201s at really cheap prices but, unsurprisingly, they're generally all fakes. Typically they're not even JFETs but cheap BJT transistors that have had the J201 designation printed on them - it is easy to test them with a transistor tester such as the DCA75.
Looking at the feedback for many of these sellers, they often get positive feedback because customers see that they have J201 printed on them and assume that they are legit. They typically also have some feedback from customers who have actually tested them before leaving feedback and discovered that they are fake.
I am hoping that my feedback will be reinstated but I am very disappointed to see that the feedback I left for such a seller is no longer visible, presumably because the seller requested that it be deleted. While this is not a high value fraud (I'm out of pocket to the tune of about £8), it is widespread and should be stamped out.
I would be interested to know if anyone else has had a similar experience.