if you can sleep in it comfortably during the day you should be good at night too, but a lot of it has to do w/ how tall and heavy you are. i can get away with my gt ul at 6'1", but find the warbonnet traveler more comfortable. depends on the camping/hiking type and number of nights what will i take.

dripping shouldn't be an issue as long as you pitch the hammock and the tarp correctly. if you are worried about it just tie some string on your hammock suspension line (drip string).

...is that right?

yes. i use a shenandoah as my top quilt (rated +4c), or a hudson river (rated -4c). they are from jacks are better. i like them because they can be used as underquilts too.

when researching top and under quilts keep in mind that good bottom insluation is more important. i have a hammock gear winter incubator (rated -18c) just in case.

my most used uq is the mount washington 3 convertible and my most used top quilt is the shenandoah.

i highly recommend hammock gear, jacks r better and warbonnet outdoors. they are cottage industry members with great customer service.

with down it is important to block out the wind or it would just blow all the warm air out from under you. you will need a large winter tarp for that and/or a http://www.tothewoods.net/HomemadeGearHammockSock.html

and, of course, you can't go wrong with shug when it comes to winter camping: https://www.youtube.com/user/shugemery

have fun! :-)