I'm not sure if I understand what you mean, unless you refer to multiple files which are very similar. If RAR is some sort of compressed "version history" storage, then it will - of course - be better than both ZIP and SIT. However, you will rarely see a Poser package suitable for that purpose. This is actually what I wrote above - pick up the right mix of files, and you will get every result you like. I'm not into doing a scientific research here, I'll leave that for serious magazines running giant tests. All that I did is to pick up some well known realworld Poser files to get a quick idea. OK, multiple files - I just took the complete Vicki library folder (PC version), 57 files altogether, mixed bag of poses, character, thumbnails, etc. Uncompressed: 3582k ZIP: 840k SIT: 636k (76% of ZIP) RAR: 688k (82% of ZIP)