I sure can't fault your research! I have the Alpinlite (the wide version of the Ultralite), and have been delighted with it for two years now. I have two friends who got the Alpinlite on my recommendation, and after their first trip into 20 degree temps a couple of weeks ago, they're equally delighted. Another buddy has the Ultralight, and he has nothing but good to say about it.

The full down collar (front and back) is one of my favorite features. The two sets of cords (one controls the collar, the other controls the hood area) sometimes are confusing inside the bag in the dark, but one is flat cord and the other is round, so you figure it out pretty quick.