That someone was right - you'll lose what you had on the drive if you move it to another unit.

Obviously the choice is yours to send it in but if it is staggering and stalling all the time it is not going to fix anything... I had the same setup and had all sorts of locking / staggering problems... I sent mine back, got a new one and had the same problems... I then sent the external drive back and got an internal... The problem changed from lots of locking to less locking but it also changed from some staggering to lots of staggering... Basically, once under 70% available space on the drive it goes haywire... If you restart it you can usually get 30 or so trouble free minutes but if you hope to run it with any tolerable level of staggers and locks you will have to keep it well over 75% free... Well, at least I do... My guess is that the DirecTV software is just terrible and will not run with any proficiency until it is corrected... It is true that with the original drive there were far less problems but with the only real use of the unit being the added HD capability - what good is the stock HR21 without the drive upgrade?? A user would be crazy to leave the ease and comfort of the HR10-250 with the near perfect TIVO system...

Good luck with whatever you decide...