My neighbour is a member and she likes it a lot, even though she says that she doesn't have a great voice. Another lady I know is also a member, enjoying the experience despite having to work hard at learning the songs. They sing at local charity events and sang at Wembley Arena in the mass national event. There was a series on TV about Rock Choir and the Wembley Arena concert [on ITV in the winter?]. If I remember rightly, it is a franchise business so much depends on your local promoter/choirmaster. Some groups are large and some are small, at least at the start. I seem to recall it's £10 a night but no doubt, all that sort of information is available locally.