Dramastic Audio Obsidian 500 by mike-661
First off, I have used just about every single compressor that anyone would ever consider using on a mixbus...
The Dramastic Obsidian has provided a polish to mixes that is what I've been looking for. It does not sound just like an SSL bus compressor. It may be a cousin of the SSL mix comp, but it's results are different and feels to me more like a "VCA mastering compressor".
Recall is incredible on this as you can guarantee the exact settings each time.
There may be times where I choose another bus compressor for different flavor, but the Obsidian has impressed me and many of my clients enough to say it's my favorite compressor for modern mixes (esp. pop and rock mixes).
BTW, there are 4 transformers in this beast. I don't know how these guys made such an amazing compressor fit the 500 series format so well.