personally, I use it for my general shit, questing alts etc. for pvp/raiding though they're "ok" but not ideal.
Using my hunter as an example my dps is about 10-15% lower with the default cr in raid situations over using tuanha's CR. Plus Tuanha's is a lot easier to configure in my opinion, Still haven't gotten the default DK routine to stop blowing every def cd it can find at the drop of a hat <.<