I used the Sanho device after a trip to Portugal. Personally, I feel better with a backup because cards can go corrupt on you. (See my other thread on this site about that.)
Last thing I wanted to do is travel with a laptop, and maybe it is just me, but the way customs keeps asking you "are you travelling with a laptop?" kinda creeps me out. It felt good to say "no". Also, I found overseas, if you need something for e-mail, etc, get get a small tablet or th elike.
I bought the Sanho because there was no real alternative, but it does have it's issues. As others have pointed out, battery life after you download a 32 GB card is pretty bad.
Another issue is, memory cards might be cheap here (in the USA & Canada), but not overseas, and that is assuming you can find them to begin with. My personal experience, on the island of Sao Miguel, Azores, I found one store that had high quality memory cards, and SD cards only. A really good SD card in teh 32 GB range here in NA that might sell for around $40 US was 40 Euros, and roughly speaking, one Euro = $1.40 US or $1.50 CDN, give or take. If you are like me and liek comapct flash cards, I found exactly one old AGFA film CF flash card, 16GB, old, old stock, and that was almost 40 Euros.
so to me, if the trip is important enough, you need backup. one last thing however. The Sanho was, to me, pretty expensive. I bought the shell and installed my own 1 TB drive. Their 1 TB drive version was (is) around $600 US or more,a nd for that price, why not just buy a small laptop/notebook of some kind and an external hard drive for backup?
If you want to make something like this work, you have to keep the price point, IMO, below the cost of other alternatives. Otherwise, I don't think most people would buy one.
good luck