Rated 5 out of 5 stars
Here is what I experienced: I did not see any price-comparison feature until I visited Amazon.com, when I was prompted with a choice whether to enable this feature or not. If I choose "No', I should not see this ever again. But I did choose "Yes", and it turned to be kind of useful to me. Also, I noticed that I can disable it anytime I want. That is "opt-in" in my dictionary unless you had a different experience.This review is for a previous version of the add-on (188.8.131.52-signed).
The best! Rated 5 out of 5 stars
I have been using this add-on for quite sometime, and are very happy with how it has kept on improving. And I have made to donation to thank the developer for providing something truly useful for free!
For the guy slamming this add-on: Jesus, talking about over-reaction. Haven't you notice the feature is opt-in? If you do not like it, do not opti-in! I personally find it useful sometime.