USB is capable of sustained transfer rates of over 30mb/sec in theory, that's more than enough to stream HD video from, yes sata (and esata) are quicker and the best option, so if you do need faster transfers, why not convert a sata port to esata for the £2-3 involved or push the boat out and spend £8 on a pcie sata card with an esata port. Next step up would be a self build NAS using one of the many available bespoke distro's (or you could do it yourself) depending on your needs, something like a 1037u, small PSu and a cheap case will allow you lots of expansion options and you could re-use the drives from your old case. It'll also give you a lot more options going forward when/if your needs and storage requirements grow.