Rated 5 out of 5 stars

Cannot install the 11.0 update in Firefox 3.5.7, which is the current (03 Feb 2010) up-to-date version of the browser. Other than that, TamperData is a valuable tool for diagnosing web application behaviors. It's reliable and straightforward and (other than the current installation problem, which I'm sure is just a mistake in its packaging) it's never done anything "weird" to me.

This review is for a previous version of the add-on (11.0.0).