Other than having to format the second hdd, there were no issues at all. I've since bought another one, with a lower spec, and had it up and running, complete with files transferred in 90 minutes
Just tried all the FN keys, and all work as they should. The only problem I've found so far is that every time I enter my password, it's rejected - until I enter it a second time. Oh, and I'm finding it strange changing from a 22" PC monitor to a 15.6" laptop screen!