Seems that not many are looking at the "Pads" sub-forum - or maybe this is just a dumb question - but I'll give it a try here.

I am thinking of trying a pad in my double layer Ridgerunner - just to see how it effects the lay - and also to have an option for 'going to ground'.
Considering that I lay 'down the center' I am wondering if a mummy shaped pad would work as well as a rectangular. There is some weight savings with the mummy shape and the benefit of flattening the bottom slightly would probably be the same in the shoulder area.
Would a mummy pad stay in place as well between the layers?
Other considerations?