The comics i tried on my 6inch 505 didnt work very well, the images were good, but the text baloons\speech was barely readable.
If you could post an example(anything free to distribute) of your brother's comic books i'd be happy to try it out for you. What I tried didnt have the large text that the link you posted has.
Here is the Eco reader Harry mentioned, its 6inch, and has australian warranty and tech support
