I like the Kelty Cosmic down bags, they are good enough for casual use. About $109 for the 40 degree which is very light and packs small, the 20 degree is around $150. I find I use a thin 40 degree bag 90% of the time. I gave up on packing synthetic bags, they just take up too much room. I have a Kelty bag that weighs well under 2 pounds in the long version and its big enough to cover my 6-4 tall self with 50" shoulders.
Even the best syn bags take up at least twice the room of a feather version..
I still prefer the Exped Syn 9 DLX pads, been using them since 2007. Nice and warm, built in pump, 3.5 thick, big enough for my large ass. Good warranty.