I have just used my winter bag inside my hammock with my winter UQ in my trips reaching the -30* nights.
I made a DIY winter hammock that has no bug net. Messing with the additional size of the bag, extra layer of clothes, etc. is enough of a challenge without trying to deal with the bugnet - either zipping or keeping it out of the way.
My winter UQ is oversized so that it gives the hammock a taco effect. The sides actually come up about 6 inches higher than the side of the hammock. I can place additional clothes or shed clothing inbetween the hammock and UQ, which makes it very convenient.