Today's high-loft down is amazing.
When I first pulled my Hammock Gear UQ and TQ out of their stuffsacks I was impressed at how much ......pressure the fill exerted when I would compress a handfull. Far better than teh 550 fill of the "old" days.
That said, I believe it is best to minimize the amount of time any down fill is stuffed. As to just how much life is lost with each compression/expansion cycle, I have no idea.