I just tried my first spin class last night. I have a trainer for my road bike but frankly after about 30 minutes on that thing I am looking for my hand gun to blow my brains out.
I went to a Golds Gym last night and they had Lemond machines that were new, and seemed to allow for a lot of adjusting for fit. I wasn't able to use my own pedals, but one side of the pedals on them allowed for SPD cleat shoes so I used my MTB shoes.
I did like the workout better then using my trainer alone. I found that the class atmosphire and music made for a more enjoyable experiance. The instructor had been told by a friend that invited me that I was an ex-pro racer and still raced mens masters so she was conserned it wouldn't be enough of a work out for me. I was told she is new at teaching these classes with 6 weeks experiance. Based on Koffee Browns comments I would say she had a good grip on these classes. The instructor did indicate that each rider should work to there level so I ran a higher revolution then most but I sure didn't think it was an easy workout. My H/R monitor indicated I was spinning at 80-90% of my max H/R so I did what I needed to do.
Over all I felt it was a great experiance. I think I may get involved in doing these 3 days a week as the weather gets colder to keep my fitness level up.