The best one I have ever used hands down, is this one:
http://www.uaudio.com/media/assetlibrary/p/r/pre_multi_hq.jpg I know not everyone wants a UAD card, but man, honest when I tell you, nothing compares to that in my opinion. It's so seamless and transparent, you have to really jump on it to have it ruin something. I've tried quite a few of these in my time and this just (as well as other UAD tonality compressors) obliterates the competition.
I give the LP 64 MB a pretty high grade too. Just use smaller ratio's when using it than the 2 presets give you. When using similar settings used on my UAD on the LP 64, it really did a nice job. I like it better than the Waves MBL's and the other 3rd party plugs available that do this sort of thing. The good thing about the UAD is, it polices to the point of hearing it but not to the point of ruining anything with artifacts.
-Danny