I installed InvisibleHand a little over a month ago. In that time I purchased two laptops, made mulitple car rental reservations and purchased other items online. Only once did InvisibleHand provide me with a deal better than what I already found online. It's still a great concept and I'd be willing to keep the add-on if it had a toggle switch so that I can disable it with one click when I'm not looking for a deal online. The pop-up from the add-on is distracting, and while you can temporarily minimize it, anytime the page refreshes, it pops back up and obscures my view of the website I'm visiting.