Currently in the summer I use a 3/4 length zlite pad and then use my current backpack under my head and shoulders. I could save weight by getting the Arc Haul Zip but would I have to then start carrying a full length pad which would cancel out the weight savings? I guess my question is, is there any reason that I couldn't use the Arc Haul Zip as part of my ground insulation in the same way I was previously using my Osprey Talon?