Hi there,
I completed VCD before the new study design came in, but I'm going to respond because these boards lack activity.
I think 1/2 gives you a nice base to work from. At least personally, my 3/4 folios wouldn't have been as good had I not done 1/2. It may have changed, but in 1/2 there was a fair bit of emphasis on mastering the various technical drawing techniques, which becomes particularly handy in 3/4. But strictly, I certainly wouldn't say that you
need 1/2 to do well in 3/4.
As for your second question, my opinion is probably skewed. Going into the exam, I was sitting at 100%; VCD was easily my best subject during the year. However, I didn't study as hard for it as other subjects (due to a relative lack of resources), and it ended up being my worst subject.
Whether or not the subject is difficult is, well, subjective (pun semi-intended). From my experience, it is very time-consuming but not particularly difficult in the sense that Spec or Chemistry might be. I did VCD with the intention of doing design at uni. That didn't eventuate and, whilst it was my favourite subject at the time, in hindsight I wish I did something else. If I spent half as much time on another (non-folio) subject as I did VCD, I'm rather confident that I would have been better off (purely in ATAR terms).
If you're interested in design, absolutely do it. If you're not, and you're looking for an 'easy' subject, I wouldn't choose this one.
Best of luck.
