With WinRK, you don’t get the same legacy format support as WinZip, and the extensive configuration options are confusing by comparison. Your reward, though, will be the best compression ratios bar none. Opt for standard ZIP64/WinZIP AES-compatible archives and they’ll be 10 per cent smaller than the competition; opt for the proprietary RK format and they can be 50 per cent smaller. Of course, it takes time to get the world’s best compression ratio (more than an hour to reduce a 40MB file collection into a 3MB miniature), but there’s plenty of scope to balance the trade-off between speed and size. A good GUI and more than adequate encryption round off an exceptional package, which is spoilt only by the value proposition of open-source products like 7-Zip.