I enjoyed the book, it's very detailed, calling upon the case files and presenting them in an order you don't experience when browsing links on a web site, and even if you don't agree with the cause of the hikers' demise, which I would say is possible, but no more probable then other alternatives, with only the "it's plausible" validation of a Bulgarian pathologist to evidence it, it's still worth buying for a Dyatlov obsessive.
I'm sure most people will opt for the download, which is the price of a takeaway, and if the revenue helps part finance this site, which like any other has overheads to meet and no advertising, so that one labour of love helps finance another, then nobody should feel robbed if they don't agree with the book's conclusions.
The only issue I had with the book is that it builds a conspiracy but then concludes in the final chapter that they died in a way which was nobody's fault, so that there was no real need for any cover up in the first place. This plot twist at the eleventh hour was like the ending of Lost.