The Jagwire KEB-SL is as close to compressionless as you can get without going to the stuff made out of metal links*. I'm currently using the cheaper CGX-SL, which is spiral wound and lists itself as "low compression," and having used both, I can tell the difference. I'm using the housing with TRP Hy/RD brakes, and I get a little bit more lever travel with the CGX, but the feel and modulation is still good-- add to that the fact that I got a 10M shop roll of it for $17 and I have no complaints.

*who knows, maybe the Shimano BC-9000 is as good or better, but that is some crazy money for them there cables.