They are an excellent tool to combat noise. But depending on several factors you need to determine where it's going to get placed. In many situations, you may require two of them. One pre and post. Cost wise either the Boss NS2 or the MXR Smart Gate can be had for your money used. I prefer the MXR myself. When it comes down to implementing it, do some research. There are a lot of resources out there on where to place gates.