The HR-20/21 DVR's from DirecTV will allow you to attach an external drive, say a 1T eSATA, and have most all of the space you'll need.
To Direct HD or Not to Direct HD or go Surewest ?
Here's the situation. I want to go HD, but I don't want to lease the equipment since I won't be able to increase the drive space. I could stay@480p or go to Surewest, purchase a Series 2 TIvo and the HD version(a Series 1 won't work with Surewest's service). I could also purchase a used DTV (HD)Tivo and do without the HD channels that I won't be able to receive.