Don't assume that an underquilt will be less weight than a pad. I have a 20 F underquilt that comes in at 15 oz. from a well known manufacturer and I have full length pads that weight less than that.

As to the packability issue, that may be true but again, not a guarantee based on what you get or may already have. Just something to consider.

That's all for now. Take care and until next time...be well.

snapper