climashield combat and xp should have a higher warmth to weight ratio than PG 3d or delta. clo value is really all that matters, the higher the clo value, the less insulation you will need for a given warmth, the smaller it will pack. pg3d in particular falls well below the other 3 in terms of clo, so you will need more of it and will end up with a heavier bulkier version. i don't think pg delta is available for diy, which leaves the climashield as a better option over the pg3d