That's correct, you can get the OTA HD and SD stations with the HD DirecTivo.

One thing to keep in mind, that makes the HD DirecTivo different from the Samsung unit I sold: The DirecTivo will only decode digital OTA stations. In the two places I've used the unit, that didn't make a difference because all the stations I cared about would dual-broadcast in analog and digital. But if it's critical for you to get analog OTA stations, then just know that the HD DirecTivo won't decode them and you've got to use the TV set's tuner to watch them.