I posted some other comments in this thread - unless they've significantly improved the software in the past year I would 100% recommend against it.

(Also, a lot of manga gets distributed through proprietary apps now so an iPad is probably your best bet anyways, at least if you read the serialized version and not the tankoubon releases...)

The eReader functionality is... poor but usable.

EPUB rendering is slow the first time you open it, and notes and highlights get lost when you change text size.

On the other hand, PDF rendering is excellent. I make it a point to buy PDF versions of ebooks and have had no issues using it like that.