The C64 demo didn't do much for me. By all means, nice colours and design, but displaying animations never impressed me much.
Risen from oblivion, on the other hand, is quite impressive. AFAIK, it's one of the very few demos that actually use the full 64K VDC expansion on my C128. I seem to recall that this demo also utilizes the 2MHz mode quite cleverly.
I have ridiculous amounts of respect for the C64/C128 coders active today.