I can personally say from the classics that I have tried, they have amazing form and technique. I used to workout to Cathe Friedrich DVDs and lift semi-professionally (Body Building) and from what I've seen, it's the current Firm selection (Firm Express) that has poor technique and form. To the point the exerciser is using momentum.
As for the original question,
The Classics tend to use heavier weights than the non-classics. However there are plenty that focus on light weights with faster movements for cardio endurance more so than strength. Workouts like The Tortoise, Tough Tape, and Cross Trainers Strength are workouts were heavier weights are used. You get the best of heavier lifting, cardio, and some 4 limb work with lighter weights for a higher calorie burn. It's like packing 2-3 workout sessions into one.
Progress not Perfection
Today I am the Tortoise. I used to be the Hare but learned that I win races far more often at a slower pace!
Whether I finish the race first or last, all that matters to me is that I finished.
Remember you are currently someone else's goal weight and/or size!