You could go with a combo of Single and
quad disc cases and be able to do multi-disc games in the same.
Shenske's got the pros/cons for the 8-disc poly pretty well.
Pros for the CD Sized poly are it's smaller size which takes up less space, and they're a little (not much but every little bit helps) cheaper than the 8-disc poly cases. On the con side, thicker manuals may not fit into a quad case, if it's full of 4 discs too and as Shenske mentioned while the cd poly cases are smaller, the 10mm spine means less real estate for logos, where the 8-disc poly is a 15mm spine.
Overall all of the options (the 2 you linked to and the additionally one I added) are all poly cases, so they've the same durability advantages of plain jewel cases.
Additionally we've got threads going for both the 8-disc and CD poly cases so should have some cover options available for both.