If your case supports it behind the motherboard tray and modular psu makes a huge dif, also you can dump spare cables in the hard disk bays if not using them all. You will need a 8pin CPU extender wire but you should be fine otherwise with the rest
as people have said put as much as you can behind the tray and use zip ties, i also use sticky back cable tie mounts so i can put cables where i want. soooo many cables.....
I would say build your own. This is what I did. You can get pass-through and terminal sata power connectors that push down onto the lines. Soldering iron, heat shrink and proper matching guage wire and you are all set. And the upside is you can change the colors of the cabling. I did all mine in black for a more stealth look.