Your mileage may vary, of course. The majority of ebooks I've bought have come from Kobo, and have been painless to buy. Account setup is a one-time thing. I've bought books directly from the device and from the website. Easy both ways, imho.
I've never bothered with ADE for Kobo books, because I don't need it for kepubs. I use it extensively with library books though, and find it painless. Account setup is, again, a one-time thing.
|