Like Chris says its personal. I have this bag in black:
http://www.dakine.com/sport-packs/photo/sequence/
Plus points for me is that Dakine make normal rucksacks and so people will not realize you have a couple of grands worth of camera equipment in there. Plus it looks cooler (to me). Whats more it has a removable camera block so I can use it as a smaller camera bag and a normal rucksack. Probably less camera orientated than a Lowepro though, but a nice balance.