>>2671428Best is pretty subjective. Do you live someplace that considers 2C cold, or does it need to get down past -10C to get out anything thicker than a fleece? Where I live we always get below -17C for at least a week.
Something like the 650 from REI is down, and usually less than $100, and lasts years. For me that's the sweet spot, but I'm not going winter camping, which might change that equation.