I just wanted to chime in for owners of MSI Z77 motherboards. Might apply to the MSI Z87s, too, not sure.
I have the Z77 MPOWER (which looks incredible in this case, btw). A lot of the MSI Z77s ATX motherboards have a similar layout. I just wanted to let people know that while the front I/O cables are too short, the USB 3.0 cable and the front audio cable are just fine for our motherboards.
I wasn't clear on exactly which cables were too short, so I bought extensions for all of them.
My unnecessary purchases and experience is your gain, folks.