would fit the bill. In my opinion, they're the best alternatives to WinRAR, but even then, WinRAR is too much WinRAR. Did you give a look to Zaine's review in the site? Although it's a bit outdated, most of the points mentioned there are still valid today.
I don't think anything could go faster anyway. By some strange phenomena, ZIP decompression in other apps tend to be quite slower (and compresion... ufff, it's even worse). And RAR, well, you said it yourself, it's programmed by the RAR algorithm creator, so it can't get much better (not without compression support, of course).
If you only want decompression support, check up Universal Extractor
. Universal Extractor is a monster, it can decompress everything, but ExtractNow is prettier and it's quite more elegant (Universal Extractor cheats a bit regarding its algorithms decompression implementation)