Well, I'm news to this forum....and seeking I've found this topic...
Well, I you're looking for a program with a good compression and speed I suggest you to use WinRAR....it's the best doing that job.
But if you're looking for the BEST compressor available,regardless the time, you must seek WinRK for compressing multiple files and PAQ8JC for single file compression.
Both programs are the BEST COMPRESSORs that you're asking for.
I'm not a guru in these matters, but if you want more information about compressors you must see this link:
http://www.maximumcompression.com
Sorry if I can't post links to anothers sites.
See ya!