The 501, 508, and 721 are the only ones you don't pay the $5.00 DVR fee. Even if you have the 301 plugged into a phone line you will have to pay the $5.00 a month for a second IRD. With 522's going for about 150 - 200 on ebay just get that. You would pay the same amount as having a 508 and 301 on your account, as long as you have a phone line into the 522. With the 522 you would have DVR on both tuners. Then you could use your DP44 and a seperator and not have to run another line.