Any suggestions (for the OP and I might be a little interested too ) on a general purpose budget software compressor?
The DBX 163 is dirt cheap, fail proof, and sounds good on a variety of things. It's my go to for kick, bass, and rap or hardcore vocals.
I think that the RNC is more for transparent compression (especially in Really Nice mode), and the ART has just a bit of color to it.
I would also go in the box for compression. I really liked vareity of sound's compressors in a 32 bit format for free VST ware. They don't play nice with Cubase x64, although J-Bridge is supposed to fix that.
As far as hardware comps, almost anything in the under $500 range should have one knob labelled "Suck" and one knob labelled "Mud". Turn it up for more. But, as with all things, YMMV.
obviously you've never heard an elysia xpressor 500 then? it's better than any of my compressor plug-ins and I own some really great plug-ins, none of them come close.