I bought my black bebe trench last fall, and I LOVE it. It's perfect for the spring weather, and it's classic enough to go with everything and every season, but the design is unique enough to be fun and interesting. The button design is futuristic looking, enough to give it a twist and make it stand out, but it's still well within the realm of a classic trench.
The belt around the waist (that's long enough to wrap around me twice) is a nice touch, makes me look slimmer, but sometimes it's frustrating because of how long it is.
As far as size goes, I purchased a small and it fits perfectly. Typically I wear a medium though, and even the extra small of this coat fit me decently.
I haven't had any buttons come off yet, but one is a little bit loose. Other than that, I have no complaints whatsoever! It was regularly $98, but I was able to get it during one of their 30% off the entire store sales, so I saved a ton of money. I love all things bebe!