I've used my Qu-16 with both a Seagate 500 gig 7200rpm drive and the Sandisk Extreme USB sticks. Both have worked flawlessly, but I adhere strictly to the factory recommendations on formatting and recording operation.
I also use the USB B output into a Macbook running Nicecast for live streaming for remote broadcast.
So far, so good.
Update: I recorded a show using the Qu16 and the WD Ultra Passport, and it all worked great. It just didn't like playing back files recorded elsewhere and copied onto that drive. The files recorded by the Qu16 play perfectly!
