Speed optimizations, 64-bit Windows support, AES-256 encryption for ZIP archives...
New in v4.5x: Speed optimizations for LZMA, Deflate, BZip2 and unRAR; AES-256 encryption for ZIP archives; multi-threading mode for compressing to .ZIP archives;
Release Notes - Last Updated: 05.06.08 (v4.58 Beta Release)
Pros: Free (open source), can offer better compression through its own 7z file format
Cons: Can have problems unpacking troublesome files in other formats, doesn''t offer compression support for all formats (unpacking only for RAR, CAB, ISO, ARJ, LZH, CHM, Z, CPIO, RPM, DEB and NSIS formats)
