It does tend to slow down my browser at times, so I have no choice but to remove the extension whenever that happens. It is, however, quite good as a drop list notification app for my Amazon purchases. I am rating it kind of low as I don't get to use it for its intended purpose, which is for coupons and rewards, as most of the stores I'm interested in are not a part of the program. When it is, most of the coupons don't even work. I am not sure if I'm just THAT unlucky or what.