In looking at our recommended top travel wallets it becomes clear that these things are BIG. Starting at 4" x 9" (10cm x 23cm) and going up to as large as 6" x 11" (14cm x 26cm) and everywhere in between these are not what we think of when we talk of "wallet". The idea is that if you can get all your required items in one place, then everything will be available when you need it, whether it's at the airport, hotel, customs, passport control, etc. Some travel wallets even have a small, built-in pen for use when filling out forms. How many times are you given a declaration/customs form on the plane as you're descending, but don't have access to a pen? Yeah, me either, so annoying. So the advantage of having your travel documents with you is attractive, but at what price? We will get into that discussion, but let's hit the obvious issue, is it really a wallet?
A "wallet" is defined as a pocket-sized, flat folding holder. The problem with this definition and the travel wallet is size. These travel wallets are monsters! Maybe if the pocket you put them in is your coat or jacket pocket this might fly, but they won't fit in your pants pocket (unless you have cargo or parachute pants). To be honest, I find myself keeping everything travel related in a small zip pouch which I have at the top of my traveling backpack or carry-on. When I need it, I just pull it out and I'm done. I know it's safe, meaning, not in my pocket, so I do actually feel more secure.
In the final analysis, I'd have to call the Travel Wallet more of a pouch than a wallet. It sounds great, it conveys the wonderful idea of organization and consolidation, but really, it's not a true wallet. Since the separation of the items you keep in your wallet, and what's suggested you keep in the Travel Wallet, do draw a fine line between everyday and special purpose, let's review if you actually need one or not.
Maybe, as is the case with all things. If you like the idea, are comfortable with carrying a large pouch on your person or within your carry-on, then go for it. As a "travel pouch" I think they're fine, but you do pay a premium for them. Additionally, for the sake of security and the proper protocol of separating your important information, you shouldn't have all your critical documents in one place. Travel documents, cash, cards, etc. should be broken out into separate locations so in the event something is lost or stolen, you haven't lost everything (trust me, it's devastating if it happens). Thus, if you do follow this wise counsel, then a Travel Wallet really sets you up for pain and unhappiness.
In the end, I don't use them and I travel internationally often enough to see what's worth traveling with and not. However, if you find them to be nifty, keep reading where we set aside our personal views and objectively tell you which travel wallets we feel are the best.