Throwing my cat into the kettle of fish here

...I did used to use Audacity for small tweakages and getting an mp3 ready after mastering but now find its present LAME incarnation a little too toppy and glassy. I far prefer Goldwave for preparing mp3s for streaming...and I still use the excellent R8brain for downrezzing.
I was mastering with Ozone within Sonar, exporting at 24/96, downrezzing the wav in R8brain, then converting to mp3 in Goldwave...a little long-winded flow for general recommendation but what I'm used to. However, as I'm about to embark on X3PE from 6PE I gleefully espy cupboardfuls of mastering tools...so I'll probably do exactly the same as I've done with the exception of Ozone!