Compression with KGB is maybe 5-8% better than 7zip only takes an insane amount of time (3 days to compress 12Gb into 8Gb). Is it worth it? For compressing a bunch of text, yes. Everything else no. I'm sticking with 7zip for compression since it is blazing fast, can compress to any format and open any format, and has close to the same compression ratio as KGB.