I have had an external HD attached to my Hopper with Sling for quite a few years now. I'm currently using a WD black label 2GB SATA in an external powered cradle. From discussions I have seen, the powered cradle is essential to trouble-free install and operation. There may be some drives that will work powered off the native USB, but it looks to be hit or miss (with the "misses" predominating...) I will also tell you from experience that using the external HD with the Hopper can be frustrating. Especially when the external drive dies after spending time and effort moving a ton of movies to it... I'd be very interested to hear from anyone who has successfully cloned their external drive, then been able to swap drives. SInce I believe the format is supposed to be Linux-compatible (ext3?) it should be possible to use any true disk imaging program on a PC to do this, but I have not yet taken the risk of trying this. I have enough issues with the Hopper periodically "losing" the attached drive (at least once a week), and requiring a system reboot to regain it. Another frustration is the lack of folder filing capability on the external drive. I just went through the exercise of selectively purging movies from that drive to regain space. Deletion of a movie required the consensus of two of us here. If I could have classified external HD items in folders, that would have been a piece of cake: move the deletion candidates into a folder; allow 2nd reviewer to move items to be retained out of that folder; delete folder contents when done. That actually was the procedure, except that every movie to be considered for deletion had to first be physically copied from the external to the internal drive, then the review took place, then retained movies had to be copied back to the external drive. This entailed hours and hours of transfers, imo for no good reason beyond Dish never reviewing the usability of its software...