Do you mean use the storage space on the wifi router device or do you mean using the internet to save files to a cloud space. Both can be done but they are two different things. Yes this what i do. There is a risk that the drive will fail and then you may be goosed. ( I would add that I do not do photography for a living) This is fine two if you can absorb the costs into the cost of doing business plus its inconvenient. Can this be done using without your computer memory in the middle. You could if you use light room store your raw files onto one external and ligthroom catalogues to another. If your house is burning down you just need to grab one.