I got a small bonus at work and I want to use use part of it to grab a quality top quilt. I currently have a sleeping bag that the zipper broke on and I sewed a footbox into it.

I grabbed a used 20* HG underquilt and I'm thinking of the 30* Econ TQ to go with it. What I'm really wondering is what the pros cons of the sewn vs zipper footboxes are? Your thoughts?