You probably have not been through details.

Unless you have computer of 1970s, decompressing wont take any time (i mean negligible). But bandwidth and network technology can’t compete with the CPU power.

Conclusion:
Its always better to use gzip, unless you expect very old version browsers to be used.

Damn this is good.

It reduced the page size from 9 k to 2 k.

Just wanted to note that this really depends – while the file will obviously transfer faster, being much smaller in size and taking less bandwidth, often it will actually take longer for the page to load as the content must be decompressed after transfer. More info is available on php.net.