HTTP compression methods

I wonder if anyone has evaluated the zlib compression feature in the Windows version of PHP (enabled by setting zlib.output_compression in php.ini) and compared it with the performance of the builtin HTTP Compression in Microsoft's Internet Information Server. I found a discussion on this very list back in 2004, in which the statement was made that zlib compression is dangerous because of browsers that don't interpret the compressed data correctly. I wonder if this situation is different now, since buggy browsers such as Netscape 4 are hardly ever used any more. -- Thank you, Lewis Kapell Computer Operations Seton Home Study School