I am not familiar with the SS UQ, but the HG should have DWR on the shell, which will help keep the moisute out of the down, unless your talking about just the outside being wet/damp. Most of the ti e, I have left mine on, but can't remember it raining alot during the day. Most times, the rain came through at night and the days were fine.
I'm a member of PETA!!!!