This morning, I watched parts of Part II and Part III. The first thing I noticed about Part II was that colors are more vibrant than the original DVD.
Like Part I, it is also a little brighter with a little more contrast. It still suffers from the same graininess.

As for Part III, it looks very good, but so does the original DVD. I found even less difference from it and the original DVD version.

One other side note, the set came with a $10 rebate that I didn't expect. So for about $50, the Blu-ray collection is a great deal.