It all depends on the situation you're going to use it for because no one bag does it all.
If you want a camera bag that doesn't scream camera bag from a potential theft point of view then don't buy a Crumpler imo. All it does in my eyes is say i'm an expensive camera bag trying not to look like a camera bag with lots of expensive stuff inside. I assume this because it has the nice Crumpler logo prominently displayed on it and they aren't cheap bags which means whatever is inside them probably really isn't cheap either.
My most discreet bags are a regular everyday no name shoulder bag and also a similar non descriptive messenger bag. I then insert actual camera protection or a camera bag inside them, either my £7.50 dslr insert into it (from bay 130923537197) which takes up the least room and offer fantastic protection. Or maybe my Lowepro rezo 160 or Nova 180. I even have carp holdall for the same purpose because they are built like tanks and have lots of room in them (plus cheap and waterproof).
That option gives me the most discreet solution and plenty of additional room for regular stuff that i might want (usually have my 3 kids with me so the extra room comes in very handy).
If i need more kit and less extra then i stick with my Kata 123 go 30 which has a lot of room, comfy(ish) and you can draw a camera quickly from it.