I used one last time on Florida Hang 2 down to ~25 with only cold feet. It was inside the hammy not outside. And I had my Sleeping bag around the hammock and ridgeline as a peapod.
I think the pad on the outside might not be the best choice since it is going to be harder to bend to the correct shape and you may have too many gaps for cold to enter. Inside the hammy, your weight shapes it to the hammy. There may be better choices for close to the price, if that's what your looking at.
I have used only the SB inside the hammy since then due to the coldest being mid 40's for my coldest since FH2 on Jan 2012.