Hooray! The Kata BP-502 I ordered off eBay from Canada has arrived at last. It's a tad larger than I'd anticipated. The one I looked at at PFD must have been the smaller version. After quite a bit of faffing around with the straps, it feels really quite comfortable on my back. Unfortunately I've left one lot of camera equipment at home today, so I can't try fully loading it up. But after emptying my Billingham bag into it (The 'blad and all associated paraphenalia), there is still bucket loads of space left, so I'm quite confident that its all going to fit in. How usable its going to be out in the field is another matter! Watch this space.......