I'm a synthetic user here but if I wasn't allergic to down I'd be willing to try it. To be honest I've gotten my gear wet three times in my life. Two were easily avoidable and all three were terrible experiences. I hot tent in the winter (ground dweller.. I know it's terrible but I'm heavily invested in it and not willing to separate with such a good system) and I can tell you that my synthetic bag dries out in the morning in about 10-20 minutes and my best friends down bag takes 30 minutes minimum. That's not a problem though to be honest and would vary heavily person to person depending on how much you sweat.
I do have an exped 9 downmat and I will cry like a baby if it ever gets ruined. That thing is so unbelievably warm and it packs down so small.
In winter your gear will get damp, and that is a fact. It's unavoidable that when you are in your warm sleep system there will be an area that warm air meets cold and relative humidity does it's magic making conensation. So there are ways to deal with it, but Ihe methods for ground dwellers and hangers must be different and I haven't figured them out yet. I should probably put this somewhere else but here goes. My problems with winter hanging are mostly related to the bivy bag system because a hammock sock is not the same. I use a bivy and the frost forms between the bivy and my bag. I'm not breathing into my bivy like I would in a sock and it covers top and bottom unlike the under quilt protectors. Being able to pull my bag out of a bivy and dry the frost off in 10-20 minutes in the am is essential for longer trips and I can't see that happening with a hammock setup with most peoples winter setups. I did experiment making a sort of peapod bivy with WPB but even at easy temps (20 degrees) the condensation on the bottom was horrendous. My under quilt had more condensation in that setup than I am comfortable with and my face was sticking out all night. My top quilt was very clean in the morning though. How do you winter hanging vets deal with condensation in the am? Short of sleeping in naked gun style full body condoms I don't see an ideal (workable) setup.
--If a cow laughs hard, does milk come out its nose?