It isn't necessarily high class, but just high standards.
They don't want their website being filled with shitty quality music -- it's extremely well-kept and organized.
Requests are usually pretty simple too. A listing of the allowed codec, quality, source, the bounty, and a link to purchase the album.
EDIT: Honestly, if you have any sort of understanding of transcodes, quality, log files, etc. the only real thing you'll need to learn is Spectral Analysis.
https://www.whatinterviewprep.com/pr...tral-analysis/