DVR differences 722 vs 612

So the installation is going to be happening soon today and we selected the ViP612 receiver. We don't need the dual tuner and want our own receivers to record our own shows. Aside from the single/dual tuner difference and a smaller hard drive, are there any other differences that make the upgrade worth it to the 722?

Both the 612 and the 722 have 3 HD tuners (2 satellite, 1 OTA) the difference is the 612 has only one set of outputs (all the same signal).

The 722 has a 500GB hdd vs a 320GB HDD for the 612.

612 does not have PIP capability.

Go with the 722, is (as you can see) has more recording time.