Rated 3 out of 5 stars
What would also work and be very helpful is if you just integrated your Search This Site Search Bar into Firefox 4's already there by default Google Search Bar. One less bar and still quick access to it would be very nice. Give us an option to do that at least while not taking away the actual second search bar for those that would like to keep it.This review is for a previous version of the add-on (0.30). This user has a previous review of this add-on.
The SearchThisSite search bar and the Google search bar have two entirely different functionalities. Combining the two would mean having to add an option to toggle between the two functionalities, which would be counter-intuitive.
How about combining the location (address) bar and Google search bar into one with Omnibar (https://addons.mozilla.org/en-US/firefox/addon/omnibar/)? You would no longer have the Google search bar and have the SearchThisSite Search Bar instead.