I've found Pacsafe bags useful whilst in transit and in busy offices. My laptop and phone can be locked in the bag and the bag locked to my seat or desk whilst I am in the loo, up stretching my legs or in a meeting. I've had a few attempts on the zippers with a pen but the zippers on most Pacsafes are tamper resistant. So far, I've been lucky that inflight or office theft has not been of the slashing variety.

Anti-theft bags tend to be heavier and have less usable interior space because the exterior walls have that stainless netting which makes them thicker and stiffer. The straps have steel cable in them and can be uncomfortable depending on the width of the strap and weight of its contents. The Pacsafe Metrosafe LS100 is the perfect everyday carry size for me but I find the straps too thin as I can feel the cable digging in my shoulder after a while. The next size up, LS250, post #13 above, has a thicker strap with a removable padded sock that I find quite comfortable, but the bag has much more capacity than I need for EDC and won't fit a laptop. I have and use the LS350 backpack that does fit a small laptop. The backpack straps are padded enough for a laptop, minimum accessories and everyday carry items. I would have liked the LS350 as a vertical crossbody messenger for added security as the top of the bags around the zippers do not have that slash-resistant mesh.

If you're looking at Pacsafe, their bags generally only have that protective mesh on the front, bottom and sides. The side against the body will not have mesh so depending on how one carries their bag, a vertical bag will be safer than a horizontal bag. Pacsafe also offers a few newer, more fashionable collections that somehow do not have their full classic security features. The sides are only partially covered, especially if there is a seam up the middle of the side panel. They also have more travel photography options now too.

Travelon is much much lighter than Pacsafe being made lighter fabrics and hardware. Internally, they usually feature panels that are essentially built-in wallets but lack the heavy sewn-in padded electronics sleeves that the Pacsafe Metrosafe collection has.

Hope this helps.