They had a strong presence at my university (which was a particularly crap one, so possibly you can start forming an impression on the basis of that connection). They never adequately explained why I should join, but eventually they offered it free to students so I joined anyway. They then failed to do anything that interested me ever, and also refused to take my pre-uni professional experience into account when I looked at the full membership requirements when I left uni, so I let my 'associate' membership lapse as soon as they asked for money. I don't miss it.