I have several compressors, but the only real reason is because I have a couple of pedalboards and I need a compressor on each. I have a Broughton Omnicomp, an Empress Bass Compressor, a 903 Effects Meridian Bass, and a Cali76 Compact Bass which I'm going to sell.
For a while I used the Cali. It's a good compressor, but when I got the Omni, I just found myself preferring that. The Cali has a nice sound on its own, but the Omni has a thumpy punch to it that just fits better to me. It's easier to me to make the Omni sound more like the Cali than the other way around. The highpass filter on the Omni is not adjustable, but I like its setting and don't feel like I would need to change it.
I got the Empress recently to serve on my second board. I got it for several reasons. It allows a better ability to monitor the compression (which the Omni has to a certain degree; the LED strip and the LED on the Omni just work better than the Cali's jewel LED), and it also operates at 18v internally from a 9v input (as does the Omni). I also like the color switch; i don't use it all the time, but the option is nice. I'd also agree with the assessment that the Empress is 'ridiculously transparent', which I think is fine. That just means good sound in = good sound out.
The Meridian is a recent addition that I haven't gigged yet. It's basically a Bass Dynacomp, a tilt EQ, and the harmonic distortion from a BBE Stomp all in one box. It's quite a neat little box, and gets some good sounds. The name of the game with it is color, which it does pretty well. The Meridian is a DIY kit that you can buy, but this one was just assembled and finished by 903 Effects. There's a bass version and guitar version. I happened to get one for like $60, which is not bad at all.