These libraries gained fame because the sounds were and "fat," meaning they could cut through a mix without requiring extensive additional EQ or compression. Producers often use the "pre-shifted" claps and tonal kicks (where the musical key is written in the filename) to speed up their workflow significantly.
Even with the rise of subscription-based services like Splice, the Vengeance "repacks" remain a staple in the folders of top-tier producers. mutekki media vengeance essential clubsounds vol1234 repack