For bags, it is hard to go wrong with a Billingham Hadley Pro. If the computer is slim (like the latest MB Pro) it will fit. A black or darker color is quite discrete and they age beautifully.
I really, really wanted to like my Hadley Pro because it is beautiful, sturdy, and cost a chunk of money. But it just didn't go with my preferred method of working, nor did it feel that comfortable on my shoulder.
I carry at least two cameras, one compact and one larger, usually a rangefinder or mirrorless camera. The compact goes in the front of my bag and I want to be able to access it instantly at any time. And if I'm out, I like to be able to stow the larger camera at a moments notice, like the first touch of rain or seeing some unsavoury people ahead.
The Hadley Pro design makes this difficult. The front pockets are buttoned, and are covered by the main flap, so keeping a compact camera secure in the front pocket means snapping a button shut. And keeping the main compartment secure means having to seal the buckle straps, which adds another layer of stuff to get through before being able to unsnap a front pocket. And to stash a larger camera inside, I have to unsnap the buckle straps, pull across the flap, drop in the camera, pull the flap back into place and seal it up again. Whereas with a zippered bag, there is no flap to get in the way, nor am I fiddling with two buckle straps.
If you want to carry the bag by the handle, it must be properly cinched up or the bag - and potentially contents - flop around.
And for some reason, even with the shoulder pad, the strap seems to dig into my shoulder. Maybe it's because it's not that wide, and the weight isn't spread across a larger area. The padded insert means that the bag doesn't mould to the contours of your body, either. I've tried taking out the insert but this just makes the bag floppy and lack any kind of structure. It's so aggravating.
Not to mention the first world problem of mistaken baggage: I had my Hadley Pro in a camera shop that specialized in Leica gear. Two other customers also carried Hadley Pros, and they put them on a chair. It suddenly occurred to me that if I put mine near them, they might accidentally take it. I'd have to customize it somehow with ribbons or tassels or big colourful luggage tags, just to make it obvious that it wasn't theirs.
I still have the Hadley Pro and I use it on very rare occasions, mainly to convince myself that I didn't waste my money.