I recently purchased a Rosewill RX-358-V2 BLK, sata to esata/usb enclosure which according to multiple reviews on newegg worked with HR** HDDVRS, tried with both my HR21 and Hr24 with two different HDs, a seagate barracuda 750 and a WD Caviar 1tb, neither would recognize (spit out error code), DTV faulted the HR21 and are sending a replacement and rosewill said no, we don't support, but as you're a good customer, we'll issue a full rma and pay shipping, so looking for an enclosure from the "guru's" that I can be positive will work!
(kudo's to DTV and Rosewill for the great service, "once you talk to the right person..")