I am using nightly many years and never had any problems. there was a problem 3-4 years ago with fast dial, but only because there was a problem into the verification from the mozilla site. the rest of my 25+ plugins work flawlessly and i am in version 29 or 28, which seems more like chrome, and chrome has a bad UI. generally speaking, 20 to 25 does not change a lot of things in the plugin api. The days were 2.0.1 and 2.0.2 were completely different and had many compatibility issues are past.