How do you send the program to the disk? There is your chance to see the size, unless Dish did that completely differently on the 211 compared to the 6x2/722 series. On the send-to-device page the sizes are shown instead of the duration. Oh, that's right you are not transferring, you are recording to. On the Manage-Device screen, where you select the replay, you should see the "rounded" size in MB.
Interestingly a DVD is 4GB or 2 hours in SP, of course that is MPEG-2. My mix of SD and HD averages very close to 2GB/hr.
-Ken