I have used the Downmat DLX 9 in my DD hammock and been toasty at -16*C (3*F) using a poncho liner as a peapod. I would say inflating the pad to 1/3 to 1/2 gives good insulation put is not inflated enough to ruin the lay or be too tipsy. The DLX is longer and wider than the other models but I still used a CCF pad to across the shoulder area. I did find the poncho liner peapod was interfering with the lay and on the last night rollrd it back so it only covered my foot area and was golden from then on.
Hangin' High and Dry