I want that rain poncho!!
I'm a member of Virgin. It is pricey, but if you use it enough, its okay. I currently do weights x 2 a week, spinning x 2, and run from the gym as well. In winter I use it more than that. Sadly not had much of a summer, so have kept using it pretty much the same amount. Plus there's the nice things like steam rooms and saunas as well. Its also really close to me which is handy. There's also the added bonus of being able to try other stuff like yoga and punch. Spinning is a great alternative to turbo training when the weathers bad.
Previously I was a member at edinburgh leisure.
I don't think I could give up my membership now, been going to a gym for around the last 8 years, and the benefits from being stronger from weights have only helped my riding.
A cheaper / alternative option might be to try out some of the british military fitness classes. IMO, they look really good and I've been meaning to take up their offer of a free class to try it out for ages. But downside is its outdoors – but maybe knowing you've paid and others will be there might help?