In my opinion, they are not aligned, if you order for a model that would not have had a 4K aligned original drive. I bought 2TB drives for both the Premiere TCD746320 (2-tuner, 320GB), and the TiVo HD TCD652160, from DVR_DUDE. The factory partition tables for the Premiere remain exactly as they were on a stock drive, with all the extra space tacked onto the end of the drive, with a small apple_free partition, at the end of that (which I wonder what it is there for, or if it serves a necessary purpose I'm unaware of, other than an unusable placeholder, or if it is deliberate). The TiVo HD drive is giving me some difficulty in reading the partition map. I just ASSUME that if he doesn't align a Premiere drive, he doesn't align a TiVo HD drive. He also ships the drives with old TiVo factory-installed software revisions. This makes the shipping software for the HD, on his drives, non-2TB supporting, so it raises a lot of doubt for the HD. If the 2TB Premiere map (the stock portion) had been altered, in any way, I doubt that JMFS would recognize it, and let you use the guided menus, as opposed to having to drop to the command prompt to use dd_rescue, like the 2TB HD requires, if you want to clone/copy it. I'll triple check, and make sure I'm not missing something, when I can free up the time and resources to take another look. Maybe just the stocks parts are misaligned, but the added space MIGHT be. I'll take another look.