As I recall someone did some fairly careful measuring of various sewn-through down jacket configurations and did NOT find that the increased number of quilt panels changed anything. Quite a surprise and that is why I remember it. Probably the Backpackinglite.com site. They tend to be somewhat scientific or at least are careful about measuring things and reporting results. All that being said; i purchased a "My Trail" 800 fill power hooded down jacket to replace one I lost on the trail. I had done lots of research and it was a very high quality jacket at a reasonable price. I am stoked about it and carry it always in my pack (14 ounces). I wrote a review for MyTrail but don't know if it was ever posted. it turned out PERFECT for me replacing he one I lost.
https://mytrailco.com/collections/mens-down-jackets/products/down-ul-hooded-jacket-ms