Come on boys and girls... thats an interesting question!
I know thats "strategic" info but lets face it... it's not really strategic because every "secret of the members area" of any paysite operator costs about $2,95 - a trial is enough!
An ideal members area in my point of view has more content that the person likes than he can browse in 12 hours or so! Simple as that... heheh... if he can see everything in short time why will he stay?
Take care,
Bruno