I want to stick with "reputable" and stable service providers since I plan to upload all my files. Feature wise Dropbox seems to be ahead of everyone. But want to consider Amazon as it fits my criteria mentioned above and the price is very attractive. Tried GDrive at work but not too happy with it.

Do you encrypt your files? Most of my sensitive documents are in PDF format, so I am adding passwords to them; but not sure if there is a better solution with Dropbox.