We bought a 'professional' socket set just before christmas from Halfrauds - on a job, forgot some stuff, needed it there and then. Lado used the 19mm socket to tighten up a few fixings - after the third one he managed to split the socket apart - it suddenly went, meaning he punched the side of a beam with his hand when it all gave way. Not happy. The socket looked to be made of monkey metal.
Useless.