What Dish PVRs can record from the buffer?

[video62]

My old tired Dishplayer 7200 can only record from the moment I push the REC button, so if I'm 10 minutes into something that I wish I had recorded from the beginning I am out of luck.

What Dish PVRs (current, and maybe soon-to-be-available, e.g. 522, 921) can I rewind a bit in the buffer and start recording from that point?

Thanks!

 

[Sean Mota]

501,508,721 I know for sure...

 

[AppliedAggression]

Every single dish DVR from the 501 onward.

 

[video62]

Thanks!

Sorry for the poor english tonight... very busy.

(Title should have read 'Which', not 'What'.)