Dan R.wrote a review of Western Mountaineering Apache MF Sleeping Bag: 15 Degree Down on January 5, 2014
Familiarity: I've used it several times
If you want the best 15d bag, it's either this one or the ff version. I have a few WM and ff bags, and they're pretty much same as far as quality goes, with the exception that I think ff down is a little better, but this is not based on any scientific analysis I've made, just observation. I've used this bag down to 0 f with no chills, so it's a pretty darn good alpine bag I think. With compression sack, able to get to 2-3 L in size. I use vapor barrier on 2+ day trips, or if need to get more warmth out of bag.