I'm confused. You say one of the cons is "No USB 3.0 to 2.0 adapter" yet on this page: http://www.techpowerup.com/reviews/Corsair/Obsidian_450D/4.html
you have a pic of the USB 2.0 & 3.0 adapters.
USB 3.0 is backwards compatible with USB 2.0 anyway....