As I recall from high school geography class, you lucky guys get the end of the nice warm Gulf Stream. We (Canadians from Lake Superior to the Rockies--- and honorary Canadians like Minnesotans and North Dakotans etc...) get the darn "continental effect."
But our winters sure are sunny and dry.
About pads, I had good results from duct-taping two thin pads together, hinge style. One pad was the core pad (a thin one, about 50cm or 19" wide ). The other pad I sliced lengthwise and used it to add side-wings to the core pad. So I now had a pad that was 38" or 100 cm wide with sides that could fold upward. Then I rounded the corners and sliced off unnecessary bits, and cut triangular darts or slices into the sides to help it bend. It fit nicely in the Blackbird hammock and kept me warm down to about 10* C or 50* F.
Add a thicker one under that and I imagine you'd get lower than that. Before I could do that I got a UQ as a gift. Still keep that pad for afternoon hangs. It's so light.
So far in this thread, they've been given all the respect accorded.....mattress protectors. (There, I've kept this family-friendly).
But, as we know from mattress protectors, there are some that are hard and crinkly, and others that are less intrusive. Returning to real pads, there are the thin least-cost hard blue closed cell foam ones, and then the Evasote (sp?) and then others that get, for the ground dwellers, to over 100quid / $160.
I'd guess that the expensive pads are not just different from hammock insulated by a UQ, but a comfort, not a compromise....just like some mattress covers, .....and such.
I think you need something to keep warm...and UQ is just one option. General consensus is that it is the best option, but also the most expensive.
I am new to this, so I thought I would try the pad first, and it was hit or miss for me. Some nights I slept most of the night just fine. Other nights I felt like I was wrestling with the pad all night. I will admit, my pad wasn't wide enough so I had this feeling like I had to sleep with my shoulders all hunched in or else they would touch the cold sides. I slept better with a pad in the hammock then I would sleep with that pad on the ground...but I kept wondering how much better I would sleep win the warm embrace of a down UQ
I can't compare my cold weather experience to most of the posters here. North Carolina is relatively warm until you go above 4000' of elevation. With those disclaimers in place, I've spent a dozen or more nights in the mid to low 20's (°F) with pads and never been even slightly cool. Even two of the cheapest blue Wal-Mart pads (stacked perpendicularly) worked fine at 20°F. Were they as comfortable as an underquilt? Absolutely not. Did they compress and fit within my backpack as well? Of course not.
If you are going to routinely winter camp do yourself a favor and get an underquilt. If winter camping is an unusual event for you use inexpensive pads and have a great time.
I would like to get a enlightened equipment quilt to use as a summer top quilt and it can be used as an underquilt for the winter
Borrow someone's UQ sometime and try it out,,and I think that will answer your questions about UQ's.