I'd question whether the drives are as fast as today's drives. But theoretically, this shouldn't be an issue. I've been using a esata to USB 3.0 converter on my RAID 5 and it seems to be plenty fast. Just so you know, I have two RAID 1 TB drives, and they seem to operate noticeably faster when I only use one drive at a time, and hook both TB connectors to it.
Ideally, you want to avoid any conversion boxes though. Does the sata connector you are considering not the standard one that works on all current drives?