Hi Bernie, you only need the trial version of CDS. I've just downloaded the trial of SCAL and will definitely be buying the full version. I bought the original Cricut when it was first released in the UK, if I'd have known that they were bringing out a bigger version so soon after I would have waited. I'm completely happy with my little bug and can't really justify ugrading to an Expression at the moment but if I was in your position I would definitely go for the Expression.