Are they value for money?
Don't worry, this isn't an announcement that we're going to start charging for access to the site! Over the years, I've joined a couple of subscription based software architecture groups such as the Worldwide Institute of Software Architects (WWISA) and the International Association of Software Architects (IASA). Generally, you pay a one-off fee and then you can login to the members area where you have access to articles, documents, discussions, etc.
From a personal perspective, I've been disappointed by the quantity and quality of material available on such sites so I've never really got much out of them (and hence have never renewed). So I'm curious ... what are your experiences with subscription based architecture/software development groups and are there any that you'd recommend to others?