Finally figured out what was causing so much performance problems in Firefox; 1Password extension.
I've tried completely uninstalling the 1Password application and the 1Password extension, but upon re-installing 1Password I get the same performance. I've already tried a new Firefox profile, and it works fine until I load the 1Password extension.
Since this is perofrmance related I'll mention that I tend to keep a lot of tabs open. I usually keep around 10 tabs open at a time, give or take a few in either direction.
Do you guys need the diagnostics report? I'm unsure if this contains performance related information or just crash information so I have not attached that in this original post.