Amazon gives the advantage of visibility as with a few exceptions they seem to be where most people (at least in fiction, if you're doing non-fiction I don't know) have had the most success (I hear romance does way better on B&N for indies, no clue why).
And Amazon lets the author/publisher choose DRM or not on KDP, though you can't change it without losing all sales rank etc.
And Amazon lets the author/publisher choose DRM or not on KDP, though you can't change it without losing all sales rank etc.