As a down bag, it will certainly compress nicely, but if the down gets wet it will lose its loft and insulating properties. You would want to buy a cover of some sort if you expect the bag to get wet, otherwise you might consider a synthetic bag instead. When it comes to the 0º rating, there are a lot of variables that play into comfortability (women sleep colder than men for example). As a 0º bag, it will definitely sustain life at that temp, but if you want to be seriously comfortable at 0-10º, you may want to consider a bag rated below 0.