I'm not as happy as I expected. I had the dimensions when I ordered, but it sure looks bigger than it measures. Oh well. Sometimes big is what you want. First time I tried to mount up, though, I fell over. My right leg hung up on the left side of the bag, and over I went. Like clipless pedals, I guess there's a learning curve.
A more serious problem; it's not totally compatable with the Brooks Champion Flyer. It mounts to the rear of the seat as expected, but the Champion Flyer has springs that keep it from strapping to the seatpost. Fortunately, all three straps are easily replaceable, so the seatpost strap will get replaced, either with velcro, or maybe a narrow Fastex strap. Unfortunately, the bag rubs the bottom of the springs, even without being strapped to the post. This is going to require some sort of wearstrip, and dangit, I just hate putting black electrical tape, or something, on a brand new bag. I also had to move the blinkie from the seatpost to the seat stay. Bless Planetbike for including a small clamp for this.
Anyway, if you have a sprung Brooks, this is something you might want to give some thought to. And hey, the bag, which is okay, cost more that the saddle, which is great.