I think a sleeping bag could not make up for lower R rated pad because the insulation beneath you gets flattened and rendered useless.
FWIW, I have Nemo Cosmo insulated pad that is 20" wide and it has a built in foot pump - and I like it very much.
I'd be interested at mini reviews from others on their pads.
Last edited by PedalingWalrus; 07-03-18 at 08:13 AM.