Jeff Evans

sharke
I hear great things about the free TDR Feedback Compressor on buses, might try this out later
http://www.tokyodawn.net/.r-feedback-compressor-2/

That one is OK but it has been replaced.
TDR Kotelnikov
 
Kotelnikov is better. These are great and very transparent. 
 
 

 
Oh wow I didn't know that was the update of the feedback compressor!

Wow never mind "mastering," the Kotelnikov is great on synth bass!

You can still download the earlier model but I have found the later one is great over everything yes. You can sort of slam it too and it does not seem to mind either. The sound does not fall apart.  It is beautiful over a mix just doing light conditioning. Like -2 to -3 GR and slowish attack. 
 
I have got an API2500 for mastering and love it. But I use either Kotelnikov, the API or something with a bit of mojo to it such as Klanghem MJUC. I am also liking the Cakewalk levelling amplifier too quite a bit.