Expensive, well made and probably the most practical bag for compact system cameras/bridge cameras.
Billingham is synonymous with quality and usability and the Hadley Small is a perfect example. I use it to hold my Panasonic G5 c/w standard zoom, a Sigma 19mm, a Sigma 60mm, a small Metz flash and several other small accessories.
The Hadley Small doesn't seem that small inside - in fact it's a bit of a TARDIS and it's quite surprising how much kit will fit in. That said, I think I might have opted for the Hadley Pro or Large if I had intended to use it for my dSLR gear.
The bag just looks great and oozes quality. Best of all it doesn't scream "hey, I'm a camera bag".
This is a bag I will keep and use for many, many years - long after I (and the wife) have forgotten how much I paid for it!