If a e book appears over a "Best Vendor List*, I assume the generic "best vendor guide" is okay, but I do not like it Significantly. Otherwise, "best-marketing book* is what I would expect to describe a e-book that marketed or is selling very well without having reference to it https://www.cureayu.com/blogs/lifestyle/decoding-chicken-pox-symptoms-a-comprehensive-guide-to-varicella-virus-and-its-impact-on-health