[Jeff*]

Good question ! I do not have much experience with UAD or with racks of sweet classic compressors, but I come from a couple of years using Acustica Nebula (and Acqua plugins) and frankly getting fed up with latency and CPU usage.

As I am too back on PT with an HDX card.

Plugin Alliance have lot's of stuff and the beauty as there are almost all AAX-DSP, it's easy to try all of the plugins for 25 bucks.
Black Rooster have nice compressors, Massey has the CT5, UH-E Presswerk is a powerhouse, Waves have nice CLA-76 for exemple.

Right now I am trialing DMG Audio TrackComp, no realistic GUI, but here are the models included:
E-Channel, G-Bus, 76D, 2A, 76A, 160, Zener, 2k5

I am impressed with what I am hearing, really really impressed. Just my 2cents, as I am trying to narrow down compressor that I will actually use :)