Andrew, I would recommend going for the class one if you can afford it, if your eventual goal is to become a commercial pilot. I do understand that the CAA are doing a Dick Turpin on it now, and charging something in the order of £400, but as a bullet to be bit (sic) at some stage it is one of the ones to chomp down on early.
Thinking about it, at least Dick Turpin had the decency to wear a mask..... !
Squid