I have several of these warmers plugged in throughout my house. They work decently well and the warmer itself is only around $1. They do have a setting to adjust the amount of product you want to come out which is ideal for small rooms. However, if you are like me and have some decently large rooms in your house you will need more than one in that room. My living room and kitchen both have 2 plugged in on opposite sides of the room because I feel like one is just not enough to get the smell distributed like I would like it to be. I like my house to smell good and these really do the trick (as long as you place them appropriately throughout the house). They are light in weight and I have no issues with the plug in getting in the way of the other outlet or anything like that. I do not really have anything bad to say about these other than they are only available in white. (At least that I have seen.) It would be nice to have them in other colors as well to coordinate them with my furniture and things like that.