Do you guys use gzip in your applications? Is it a major benefit? Are there drawbacks?

For what precisely? Data storage? Transport encoding?

We do. The benefit is significant but never do it on PHP side. Use Apache or nginx module. deflate works even better btw.

Correct me if I’m wrong … but isn’t deflate just gzip sans header and checksum?

Gzip is good:

That reminds me to actually go and configure my own server to use this… :)

Speaking of which. Just the other day I found out I could do this in nginx:

gzip_types text/* application/*+xml;