Topic on Talk:The big list of third-party DRM on Steam
Expack3 has addressed the drive claims while I was writing this. I wouldn't seriously consider this until some more trustworthy source has tested it directly. Obfuscation increases reads and execution overhead (since it's basically using deliberately unoptimised code) but it wouldn't need that many extra writes since a decrypted result isn't being stored permanently.
As for games using Denuvo I think Lords of the Fallen is the only one on Steam so far; confirmed cases outside of Steam are currently FIFA 14, FIFA 15 and the aforementioned Dragon Age: Inquisition.
The Denuvo website previously had a Who we work with section showing Rockstar and various others (leading to speculation that Grand Theft Auto V might use it). Either way it looks like most (all?) upcoming EA titles are using Denuvo.