Please remind me about buying Epub 3 ebooks, my recollection is that it shouldn't be a problem downloading it into Sony Reader for PC, v2.2 (and not updated to the Kobo version).
That is, it shouldn't be a problem provided Kobo hasn't changed to an updated ?? (I can't remember what it's called

) And if Kobo has changed to this updated ??, then it would mean that it could only be downloaded into ADE 3?
Also, from threads/posts over the last month or so it seems that downloading the kepub version of Epub 3 is fixed now, so that should mean that obok can handle it on entry into Calibre?
This particular ebook I don't want to buy, but it struck my attention because it's newly released, May 2015, is a Penguin and is fiction.
Without a Trace
Lesley Pearce