it works great!

Good addon, simple to use

Other extension are laggy and buggy , I make a mozilla id just to review this extension . Very nite extension.
Great works like charm.

非常好扩展，使我的课程16倍速播放

Simple but really useful

Tried a few different speed extensions/addons (including userscripts), but settled on this one.

This is the speed Add-On that will stay active when the page is refreshed. This is the only one I have found so far that is persistent. The mappable keys for speed control are awesome as well.