This reply may be a little late in coming since it was brought up nearly a year ago but I just went to WOWIO, for the first time and I am impressed with the number of titles that they have. One of the best features that they have is that you can preview the fist 5 or 6 pages to see if you like it, most of the titles are $.99 but some go higher.
I purchased 4 , at $.99 ea. just to see how everything went. The download was a little slow, the books themselves are in PDF, not my favourite but I am able to convert to cbr.
All in all a good legal source for books, you won't find a lot of the mainstream titles, but there is a lot of good reading at a reasonable cost.
I am going to pay a visit to DriveThruComics to do some comparisons.
The fact is, that the best bang for your buck is still DCM, so visit lots, download lots, and donate lots.
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