Better than others that I used

I use Far Future Expiry Header with WP Super cache, Combine JS and Combine CSS; they make a great team and are all free to use!

I use a shared Host Gator server and they have GZIP activated by default. If you enable it again in this plugin, your site will be slow, so do not use GZIP in ANY plugin. My site with GZIP enabled in plugins slowed the server down by 3 whole seconds with every page refresh/load!

Any way, this is a great plugin and easy to use. Keep up the good work and thank you!