The I have also checked the download of the free home version from
http://files.avast.com/iavs5x/setup_av_free_eng.exe.
The file size, signature date & time and Md5 sum exactly matches the file downloaded from MajorGeeks.
The Md5 value for both these files is
bae19e7f87f55674becd9967716792fe.
I don't have any real issue with outsourcing file distribution, although I personally prefer to source from the authors site where possible, and I certainly appreciate the load that is placed on download servers when a new version is announced.
Again, the main point of my posts in this thread is that some variations exist in what people are downloading from the various sites, including one where the signature is not valid, and this might be a contributing factor in why some have experienced problems others haven't