I work at a sign company and am starting to take photos of completed projects for them. I want to store my RAW files and lightroom catalog files on an external HD. I also want to take advantage of Lightroom's backup feature and get a second external HD. Thinking about 1TB of space. Wondering if all xternal hard drives can be linked to each other? For example coming out of my iMac with FW400 to the first externals FW400 then out of the other FW400 port on the first external to the second externals FW400. Does this work? Also, can anybody recommend me a reliable brand? Doesn't have to be cheap either as work is paying for it.